Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Sci Robot ; 9(89): eadi8022, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38598610

RESUMO

We investigated whether deep reinforcement learning (deep RL) is able to synthesize sophisticated and safe movement skills for a low-cost, miniature humanoid robot that can be composed into complex behavioral strategies. We used deep RL to train a humanoid robot to play a simplified one-versus-one soccer game. The resulting agent exhibits robust and dynamic movement skills, such as rapid fall recovery, walking, turning, and kicking, and it transitions between them in a smooth and efficient manner. It also learned to anticipate ball movements and block opponent shots. The agent's tactical behavior adapts to specific game contexts in a way that would be impractical to manually design. Our agent was trained in simulation and transferred to real robots zero-shot. A combination of sufficiently high-frequency control, targeted dynamics randomization, and perturbations during training enabled good-quality transfer. In experiments, the agent walked 181% faster, turned 302% faster, took 63% less time to get up, and kicked a ball 34% faster than a scripted baseline.


Assuntos
Robótica , Futebol , Robótica/métodos , Aprendizagem , Caminhada , Simulação por Computador
2.
Health Serv Res ; 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38477023

RESUMO

OBJECTIVE: To investigate the association between travel distance and postoperative length of stay (LOS) and discharge disposition among veterans undergoing surgical aortic valve replacement (SAVR). DATA SOURCES/STUDY SETTING: We performed a retrospective cohort study of patients undergoing SAVR, with or without coronary artery bypass grafting (CABG) at VA Boston Healthcare (January 1, 2005-December 31, 2015). STUDY DESIGN: Postoperative LOS and discharge disposition were compared for SAVR patients based on travel distance to the facility: <100 miles or ≥100 miles. Multivariable regression was performed to ascertain factors associated with LOS and home discharge. DATA COLLECTION/EXTRACTION METHODS: Data were collected via chart review. All patients undergoing SAVR at our institution who primarily resided within the defined region were included. PRINCIPAL FINDINGS: Of 597 patients studied, 327 patients underwent isolated SAVR; 270 patients underwent SAVR/CABG. Overall median (IQR) distance between the patient's residence and the hospital was 49.95 miles (27.41-129.94 miles); 190 patients (32%) resided further than 100 miles away. There were no differences in the proportion of patients with diabetes, hypertension, chronic obstructive pulmonary disease (COPD), cerebrovascular disease, atrial fibrillation, or prior myocardial infarction between groups. Overall LOS (IQR) was 9 (7-13) days and did not differ between groups (p = 0.18). The proportion of patients discharged home was higher among patients who resided more than 100 miles from the hospital (71% vs. 58%, p = 0.01). On multivariable analysis, residing further than 100 miles from the hospital was independently associated with home discharge (OR = 1.64, 95% CI: 1.09-2.48). Travel distance was not associated with LOS. CONCLUSIONS: Based on our institutional experience, potential concerns of longer hospital stay or discharge to other inpatient facilities for geographically distanced patients undergoing SAVR do not appear supported. Continued examination of the drivers underlying the marked shift of veterans to the private sector appears warranted.

3.
Res Sq ; 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37609264

RESUMO

Background: It is estimated that more than half of the world population has been infected with Helicobacter pylori. Most newly acquired H. pylori infections occur in children before 10 years of age. We hypothesized that early life H. pylori infection could influence the composition of the microbiome at mucosal sites distant to the stomach. To test this hypothesis, we utilized the infant rhesus macaque monkey as an animal model of natural H. pylori colonization to determine the impact of infection on the lung and oral microbiome during a window of postnatal development. Results: From a cohort of 4-7-month-old monkeys, gastric biopsy cultures identified 44% of animals infected by H. pylori. 16S ribosomal RNA gene sequencing of lung washes and buccal swabs from animals showed distinct profiles for the lung and oral microbiome, independent of H. pylori infection. In relative order of abundance, the lung microbiome was dominated by the phyla Proteobacteria, Firmicutes, Bacteroidota, Fusobacteriota, Campilobacterota and Actinobacteriota while the oral microbiome was dominated by Proteobacteria, Firmicutes, Bacteroidota, and Fusobacteriota. Relative to the oral cavity, the lung was composed of more genera and species that significantly differed by H. pylori status, with a total of 6 genera and species that were increased in H. pylori negative infant monkey lungs. Lung, but not plasma IL-8 concentration was also associated with gastric H. pylori load and lung microbial composition. Conclusions: We found the infant rhesus macaque monkey lung harbors a microbiome signature that is distinct from that of the oral cavity during postnatal development. Gastric H. pylori colonization and IL-8 protein were linked to the composition of microbial communities in the lung and oral cavity. Collectively, these findings provide insight into how H. pylori infection might contribute to the gut-lung axis during early childhood and modulate future respiratory health.

4.
J Vis Commun Med ; 46(3): 116-121, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37431723

RESUMO

Effective communication is a crucial component of patient-centered care and individuals with low health literacy face significant challenges in managing their health, leading to longer hospital stays and worse outcomes. Visual aids, such as medical illustrations and pictograms, can enhance patient understanding and memory retention; however, there is a lack in the medical field of tools for evaluating and improving a physician's ability to draw clinical illustrations for their patient. This article explores an aesthetic scale created in collaboration between Boston University Medical School and the Boston University Fine-Arts department. The scale scores basic design elements that could reasonably be improved in a clinical setting. A pilot study demonstrated interrater reliability between trained artists scoring images of varying concepts and visual quality with a Cronbach's alpha of 0.95. This scale has potential use in medical visual education and clinical evaluation.


Assuntos
Educação Médica , Ilustração Médica , Humanos , Projetos Piloto , Reprodutibilidade dos Testes , Recursos Audiovisuais
5.
Prog Cardiovasc Dis ; 77: 59-69, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36841492

RESUMO

Despite sleep's fundamental role in maintaining and improving physical and mental health, many people get less than the recommended amount of sleep or suffer from sleeping disorders. This review highlights sleep's instrumental biological functions, various sleep problems, and sleep hygiene and lifestyle interventions that can help improve sleep quality. Quality sleep allows for improved cardiovascular health, mental health, cognition, memory consolidation, immunity, reproductive health, and hormone regulation. Sleep disorders, such as insomnia, sleep apnea, and circadian-rhythm-disorders, or disrupted sleep from lifestyle choices, environmental conditions, or other medical issues can lead to significant morbidity and can contribute to or exacerbate medical and psychiatric conditions. The best treatment for long-term sleep improvement is proper sleep hygiene through behavior and sleep habit modification. Recommendations to improve sleep include achieving 7 to 9 h of sleep, maintaining a consistent sleep/wake schedule, a regular bedtime routine, engaging in regular exercise, and adopting a contemplative practice. In addition, avoiding many substances late in the day can help improve sleep. Caffeine, alcohol, heavy meals, and light exposure later in the day are associated with fragmented poor-quality sleep. These sleep hygiene practices can promote better quality and duration of sleep, with corresponding health benefits.


Assuntos
Higiene do Sono , Distúrbios do Início e da Manutenção do Sono , Humanos , Higiene do Sono/fisiologia , Sono , Exercício Físico , Saúde Mental
6.
Sci Robot ; 7(69): eabo0235, 2022 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-36044556

RESUMO

Learning to combine control at the level of joint torques with longer-term goal-directed behavior is a long-standing challenge for physically embodied artificial agents. Intelligent behavior in the physical world unfolds across multiple spatial and temporal scales: Although movements are ultimately executed at the level of instantaneous muscle tensions or joint torques, they must be selected to serve goals that are defined on much longer time scales and that often involve complex interactions with the environment and other agents. Recent research has demonstrated the potential of learning-based approaches applied to the respective problems of complex movement, long-term planning, and multiagent coordination. However, their integration traditionally required the design and optimization of independent subsystems and remains challenging. In this work, we tackled the integration of motor control and long-horizon decision-making in the context of simulated humanoid football, which requires agile motor control and multiagent coordination. We optimized teams of agents to play simulated football via reinforcement learning, constraining the solution space to that of plausible movements learned using human motion capture data. They were trained to maximize several environment rewards and to imitate pretrained football-specific skills if doing so led to improved performance. The result is a team of coordinated humanoid football players that exhibit complex behavior at different scales, quantified by a range of analysis and statistics, including those used in real-world sport analytics. Our work constitutes a complete demonstration of learned integrated decision-making at multiple scales in a multiagent setting.


Assuntos
Futebol Americano , Futebol , Humanos , Aprendizagem , Movimento , Reforço Psicológico , Futebol/fisiologia
7.
J Am Dent Assoc ; 153(11): 1096-1103, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-34799013

RESUMO

BACKGROUND: The aim of this article is to discuss the scientific evidence available on the pathophysiology and management of otologic complaints in patients with temporomandibular disorders (TMDs). TYPES OF STUDIES REVIEWED: The authors conducted an electronic search in MEDLINE, Web of Science and ScienceDirect and retrieved all the relevant peer-reviewed journal articles available in English on the topic. No time restriction was applied. RESULTS: No consensus exists on the management of otologic symptoms in patients with concomitant TMD. The scientific evidence suggests that conservative or reversible TMD therapy might provide relief. However, this evidence is scarce and low, thus further studies with larger sample sizes and better designed methodological frameworks are needed. Until such evidence is available, dentists and orofacial pain specialists should treat TMD patients using current guidelines and refer those with otologic symptoms to an otolaryngologist. PRACTICAL IMPLICATIONS: Given the wide range of potential pathophysiologies and treatments for each otologic symptom described in the TMD patient, close collaboration with otolaryngologists is essential to achieve the best patient care.


Assuntos
Otopatias , Transtornos da Articulação Temporomandibular , Humanos , Otopatias/complicações , Otopatias/terapia , Otopatias/diagnóstico , Transtornos da Articulação Temporomandibular/complicações , Transtornos da Articulação Temporomandibular/terapia , Transtornos da Articulação Temporomandibular/diagnóstico , Dor Facial/etiologia , Dor Facial/terapia
8.
Commun Med (Lond) ; 1(1): 44, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34870285

RESUMO

BACKGROUND: COVID-19 is a pandemic respiratory and vascular disease caused by SARS-CoV-2 virus. There is a growing number of sensory deficits associated with COVID-19 and molecular mechanisms underlying these deficits are incompletely understood. METHODS: We report a series of ten COVID-19 patients with audiovestibular symptoms such as hearing loss, vestibular dysfunction and tinnitus. To investigate the causal relationship between SARS-CoV-2 and audiovestibular dysfunction, we examine human inner ear tissue, human inner ear in vitro cellular models, and mouse inner ear tissue. RESULTS: We demonstrate that adult human inner ear tissue co-expresses the angiotensin-converting enzyme 2 (ACE2) receptor for SARS-CoV-2 virus, and the transmembrane protease serine 2 (TMPRSS2) and FURIN cofactors required for virus entry. Furthermore, hair cells and Schwann cells in explanted human vestibular tissue can be infected by SARS-CoV-2, as demonstrated by confocal microscopy. We establish three human induced pluripotent stem cell (hiPSC)-derived in vitro models of the inner ear for infection: two-dimensional otic prosensory cells (OPCs) and Schwann cell precursors (SCPs), and three-dimensional inner ear organoids. Both OPCs and SCPs express ACE2, TMPRSS2, and FURIN, with lower ACE2 and FURIN expression in SCPs. OPCs are permissive to SARS-CoV-2 infection; lower infection rates exist in isogenic SCPs. The inner ear organoids show that hair cells express ACE2 and are targets for SARS-CoV-2. CONCLUSIONS: Our results provide mechanistic explanations of audiovestibular dysfunction in COVID-19 patients and introduce hiPSC-derived systems for studying infectious human otologic disease.

9.
Mycologia ; 113(5): 891-901, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34236933

RESUMO

Suillus is among the best-known examples of an ectomycorrhizal (ECM) fungal genus that demonstrates a high degree of host specificity. Currently recognized host genera of Suillus include Larix, Pinus, and Pseudotsuga, which all belong to the pinoid clade of the family Pinaceae. Intriguingly, Suillus sporocarps have been sporadically collected in forests in which known hosts from these genera are locally absent. To determine the capacity of Suillus to associate with alternative hosts in both the pinoid and abietoid clades of Pinaceae, we examined the host associations of two Suillus species (S. punctatipes and S. glandulosus) through field-based root tip sampling and seedling bioassays. Root tip collections underneath Suillus sporocarps were molecularly identified (fungi: nuc rDNA internal transcribed spacer region ITS1-5.8S-ITS2 [ITS barcode]; plant: trnL) to assess the association with multiple hosts. The bioassays contained both single- and two-species treatments, including a primary (Larix or Pseudotsuga) and a secondary (Picea, Pinus, or Abies) host. For the S. punctatipes bioassay, an additional treatment in which the primary host was removed after 8 mo was included to assess the effect of primary host presence on longer-term ECM colonization. The field-based results confirmed that Suillus fungi were able to associate with Abies and Tsuga hosts, representing novel host genera for this genus. In the bioassays, colonization on the primary hosts was detected in both single- and two-species treatments, but no colonization was present when Picea and Abies hosts were grown alone. Removal of a primary host had no effect on percent ECM colonization, suggesting that primary hosts are not necessary for sustaining Suillus colonization once they are successfully established on secondary hosts. Collectively, our results indicate that host specificity is more flexible in this genus than previously acknowledged and help to explain the presence of Suillus in forests where recognized hosts are not present.


Assuntos
Abies , Micorrizas , Picea , Pinus , Especificidade de Hospedeiro , Micorrizas/genética
10.
Laryngoscope ; 131(3): 686-689, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32681735

RESUMO

OBJECTIVES: To determine the prevalence of sleep disorders in the United States and the association between sleep disorders and all-cause mortality. METHODS: A cross-sectional analysis of the 2009 to 2010 National Health and Nutrition Examination Survey (NHANES) and 2015 National Death Index (NDI) was performed. The 2009 to 2010 NHANES national household survey for adults ≥ 18 years was examined for the prevalence of sleep disorders as well as standard demographics and the presence of comorbidities (coronary artery disease [CAD], stroke, and emphysema). This dataset was linked to the 2015 NDI to associate the presence of sleep disorders with 5-year all-cause mortality. RESULTS: The study sample had a mean age of 46.1 years old, was 48.3% male, and had an average body mass index (BMI) of 28.7 (28.4-28.9). 7.1% (6.5%-7.7%) of adults reported being diagnosed with a sleep disorder, which represents an estimated 15.9 million (13.2-18.6) patients. The estimated mortality rate for those having a sleep disorder was 9.3% (7.2%-11.9%) compared to 5.2% (4.5%-5.9%) without a sleep disorder (odds ratio 1.89, P = <.001). After adjusting for age, sex, BMI, CAD, stroke, and emphysema, having a sleep disorder remained a significant predictor of increased mortality (hazard ratio, 1.5 [1.02-2.18], P = .042). CONCLUSION: This study reports a high prevalence of self-reported but physician-diagnosed sleep disorders; however, this likely represents an underestimate. Given the association with all-cause mortality, there is a need for increased recognition of undiagnosed sleep disorders within the United States. LEVEL OF EVIDENCE: 2b Laryngoscope, 131:686-689, 2021.


Assuntos
Mortalidade/tendências , Transtornos do Sono-Vigília/mortalidade , Adolescente , Adulto , Idoso , Índice de Massa Corporal , Comorbidade , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Razão de Chances , Prevalência , Modelos de Riscos Proporcionais , Estados Unidos/epidemiologia , Adulto Jovem
11.
Mycologia ; 112(6): 1086-1103, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32897841

RESUMO

In tropical and subtropical rainforests, vegetative fungal rhizomorphs from the Marasmiineae are routinely used as construction material in bird nests. Because rhizomorphs seldom produce mushrooms within nests, the fungal species involved remain largely unknown. In turn, this limitation has prevented us from resolving broader questions such as whether specific fungal species are selected by birds for different functional roles (i.e., attachment, or parasite control). To fill some of these gaps, we collected 74 rhizomorph-containing bird nests from the Neo- and Afrotropics and used nuc rDNA internal transcribed spacer ITS1-5.8S-ITS2 (ITS) sequences to discriminate between rhizomorph-forming species. In total we recovered 25 Marasmiineae species used by birds in nest construction, none of which were shared between the Neotropics and the Afrotropics. We also collected Marasmiineae basidiomes in the vicinity of nests and used ITS sequences to match these sporulating morphs with nest rhizomorphs for nine species. Basidiomes from an additional five species were found fruiting from rhizomorphs incorporated within bird nests. Finally, an additional six species were putatively identified based on publicly available sequence data. Rhizomorphs of five species were found to be utilized almost exclusively as lining material in nests. Lining material comes in direct contact with nestlings and is hypothesized to play a role in parasite control. Rhizomorphs from 10 species were used to attach and anchor nests to substrates; we matched six of those to fruiting litter trap-forming species collected in the understory. Litter traps hold large quantities of fallen litter material, suggesting that birds may preferentially use rhizomorphs that are adapted to bearing heavy loads for nest attachment. Finally, we describe two species of Marasmius-M. neocrinis-equi, sp. nov., and M. nidus-avis, sp. nov.-that are commonly found associated with bird nests and show that rhizomorph production is common across the genus.


Assuntos
Agaricales/classificação , Agaricales/genética , Aves , Variação Genética , Clima Tropical , Agaricales/isolamento & purificação , Animais , Comportamento de Nidação
12.
Am J Otolaryngol ; 25(6): 379-84, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15547805

RESUMO

PURPOSE: Review the microbiology of chronic rhinosinusitis and test the hypothesis that bacterial infections are not the predominant etiology for chronic rhinosinusitis. MATERIALS AND METHODS: Tissue cultures were prospectively collected from the ethmoid mucosa of 179 patients (94 had chronic rhinosinusitis and 85 had chronic rhinosinusitis with polyposis) at the time of endoscopic sinus surgery. All patients were off antibiotics for at least 1 week at the time of surgery. Both aerobic and anaerobic cultures were obtained for each specimen. RESULTS: A total of 263 isolates were identified (average: 1.5 isolates per specimen). Coagulase-negative Staphylococcus, a likely contaminant, was the most common isolate and was identified in 51% of patients. Forty percent of patients (72/179) grew pathogenic aerobic bacteria, the most common was Staphylococcus aureus (18%). Six percent of patients (10/179) grew pathogenic anaerobic bacteria. The microbiology of patients with and without nasal polyposis was not significantly different. CONCLUSION: These findings suggest that factors other than bacterial infection may play an integral role in the pathogenesis of chronic rhinosinusitis.


Assuntos
Infecções Bacterianas/complicações , Sinusite Etmoidal/microbiologia , Adulto , Bactérias Anaeróbias/isolamento & purificação , Doença Crônica , Sinusite Etmoidal/etiologia , Feminino , Humanos , Masculino , Mucosa Nasal/microbiologia , Pólipos Nasais/microbiologia , Estudos Prospectivos , Infecções Estafilocócicas/complicações , Staphylococcus aureus/isolamento & purificação
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...