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1.
J Neurosci ; 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38789263

RESUMEN

The intention to act influences the computations of various task-relevant features. However, little is known about the time course of these computations. Furthermore, it is commonly held that these computations are governed by conjunctive neural representations of the features. But, support for this view comes from paradigms arbitrarily combining task features and affordances, thus, requiring representations in working memory. Therefore, the present study used electroencephalography and a well-rehearsed task with features that afford minimal working memory representations to investigate the temporal evolution of feature representations and their potential integration in the brain. Female and male human participants viewed and grasped objects or touched them with a knuckle. Objects had different shapes and were made of heavy or light materials with shape and weight being relevant for grasping, not for "knuckling." Using multivariate analysis showed that representations of object shape were similar for grasping and knuckling. However, only for grasping did early shape representations reactivate at later phases of grasp planning, suggesting that sensorimotor control signals feed back to early visual cortex. Grasp-specific representations of material/weight only arose during grasp execution after object contact during the load phase. A trend for integrated representations of shape and material also became grasp-specific but only briefly during Movement onset. These results suggest that the brain generates action-specific representations of relevant features as required for the different subcomponents of its action computations. Our results argue against the view that goal-directed actions inevitably join all features of a task into a sustained and unified neural representation.Significance statement The idea that all the features of a task are integrated into a joint representation or event file is widely supported but importantly based on paradigms with arbitrary stimulus-response combinations. Our study is the first to investigate grasping using electroencephalography to search for the neural basis of feature integration in such a daily-life task with overlearned stimulus-response mappings. Contrary to the notion of event files we find limited evidence for integrated representations. Instead, we find that task-relevant features form representations at specific phases of the action, suggesting that action intentions reactivate representations of relevant features. Our results show that integrated representations do not occur universally for any kind of goal-directed behaviour but in a manner of computation on demand.

2.
Environ Sci Technol ; 57(1): 415-427, 2023 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-36562547

RESUMEN

The COVID-19 pandemic brought new emphasis on indoor air quality. However, few studies have investigated the impact of air filtration, a COVID-mitigation approach, on indoor air concentrations of semivolatile organic compounds (SVOCs). Using a quasi-experimental design, we quantified the impact of a relatively low-cost "do-it-yourself" air filter (Corsi-Rosenthal Box; CR Box) on indoor air concentrations of 42 PFAS and 24 other SVOCs. We sampled air before (October-November 2021) and during (February-March 2022) deployment of CR Boxes in 17 rooms located in an occupied Providence, Rhode Island office building. We measured sound levels in rooms with CR Boxes operating and not operating. While CR Boxes were deployed, concentrations of seven PFAS (N-EtFOSE, N-EtFOSA, FBSA, PFBS, PFHxS, PFOS, PFNA) were 28-61% lower and concentrations of five phthalates (DMP, DEP, DiBP, BBzP, DCHP) were 29-62% lower. Concentrations of five PFAS and one phthalate increased 23-44% during the intervention period, but the 95% CI of most of these estimates included the null. Daytime sound levels increased 5.0 dB when CR Boxes were operating. These results indicate that CR Boxes reduced exposure to several lower-volatility phthalates and sulfonated PFAS previously reported to be found in office building materials and products, with potentially distracting increases in sound levels.


Asunto(s)
Contaminación del Aire Interior , COVID-19 , Ácidos Ftálicos , Humanos , Pandemias , Polvo , COVID-19/prevención & control , Ácidos Ftálicos/análisis , Compuestos Orgánicos
3.
Environ Res ; 199: 111353, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34048746

RESUMEN

Many environmental justice communities face elevated exposures to multiple stressors, given biases in urban and environmental policy and planning. This paper aims to evaluate sound level exposure in a densely populated environmental justice city in close proximity to major roadways, a nearby airport and high levels of industrial activity. In this study we collected various sound level metrics to evaluate the loudness and frequency composition of the acoustical environment in Chelsea, Massachusetts, USA. A total of 29 week-long sites were collected from October 2019 to June 2020, a time period that also included the influence of the COVID-19 pandemic, which drastically altered activity patterns and corresponding sound level exposures. We found that Chelsea is exposed to high levels of sound, both day and night (65 dB (A), and 80 dB and 90 dB for low frequency, and infrasound sound levels). A spectral analysis shows that 63 Hz was the dominant frequency. Distance to major roads and flight activity (both arrivals and departures) were most strongly correlated with all metrics, most notably with metrics describing contributing from lower frequencies. Overall, we found similar patterns during the COVID-19 pandemic but at levels up to 10 dB lower. Our results demonstrate the importance of noise exposure assessments in environmental justice communities and the importance of using additional metrics to describe communities inundated with significant air, road, and industrial sound levels. It also provides a snapshot of how much quieter communities can be with careful and intentional urban and environmental policy and planning.


Asunto(s)
COVID-19 , Pandemias , Ciudades , Exposición a Riesgos Ambientales , Humanos , Massachusetts/epidemiología , SARS-CoV-2
4.
Molecules ; 24(14)2019 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-31340431

RESUMEN

Pyrrolo[3,2-d]pyrimidines have been studied for many years as potential lead compounds for the development of antiproliferative agents. Much of the focus has been on modifications to the pyrimidine ring, with enzymatic recognition often modulated by C2 and C4 substituents. In contrast, this work focuses on the N5 of the pyrrole ring by means of a series of novel N5-substituted pyrrolo[3,2-d]pyrimidines. The compounds were screened against the NCI-60 Human Tumor Cell Line panel, and the results were analyzed using the COMPARE algorithm to elucidate potential mechanisms of action. COMPARE analysis returned strong correlation to known DNA alkylators and groove binders, corroborating the hypothesis that these pyrrolo[3,2-d]pyrimidines act as DNA or RNA alkylators. In addition, N5 substitution reduced the EC50 against CCRF-CEM leukemia cells by up to 7-fold, indicating that this position is of interest in the development of antiproliferative lead compounds based on the pyrrolo[3,2-d]pyrimidine scaffold.


Asunto(s)
Antineoplásicos/farmacología , Pirimidinas/farmacología , Pirroles/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Pirimidinas/síntesis química , Pirimidinas/química , Pirroles/síntesis química , Pirroles/química , Relación Estructura-Actividad
5.
J Expo Sci Environ Epidemiol ; 33(4): 537-547, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37414869

RESUMEN

BACKGROUND: In response to COVID-19, attention was drawn to indoor air quality and interventions to mitigate airborne COVID-19 transmission. Of developed interventions, Corsi-Rosenthal (CR) boxes, a do-it-yourself indoor air filter, may have potential co-benefits of reducing indoor air contaminant levels. OBJECTIVE: We employed non-targeted and suspect screening analysis (NTA and SSA) to detect and identify volatile and semi-volatile organic contaminants (VOCs and SVOCs) that decreased in indoor air following installation of CR boxes. METHODS: Using a natural experiment, we sampled indoor air before and during installation of CR boxes in 17 rooms inside an occupied office building. We measured VOCs and SVOCs using gas chromatography (GC) high resolution mass spectrometry (HRMS) with electron ionization (EI) and liquid chromatography (LC) HRMS in negative and positive electrospray ionization (ESI). We examined area count changes during vs. before operation of the CR boxes using linear mixed models. RESULTS: Transformed (log2) area counts of 71 features significantly decreased by 50-100% after CR boxes were installed (False Discovery Rate (FDR) p-value < 0.2). Of the significantly decreased features, four chemicals were identified with Level 1 confidence, 45 were putatively identified with Level 2-4 confidence, and 22 could not be identified (Level 5). Identified and putatively identified features (Level ≥4) that declined included disinfectants (n = 1), fragrance and/or food chemicals (n = 9), nitrogen-containing heterocyclic compounds (n = 4), organophosphate esters (n = 1), polycyclic aromatic hydrocarbons (n = 8), polychlorinated biphenyls (n = 1), pesticides/herbicides/insecticides (n = 18), per- and polyfluorinated alkyl substances (n = 2), phthalates (n = 3), and plasticizers (n = 2). IMPACT STATEMENT: We used SSA and NTA to demonstrate that do-it-yourself Corsi-Rosenthal boxes are an effective means for improving indoor air quality by reducing a wide range of volatile and semi-volatile organic contaminants.


Asunto(s)
Contaminación del Aire Interior , COVID-19 , Hidrocarburos Policíclicos Aromáticos , Compuestos Orgánicos Volátiles , Humanos , Contaminación del Aire Interior/análisis , Compuestos Orgánicos Volátiles/análisis , Espectrometría de Masas , Hidrocarburos Policíclicos Aromáticos/análisis
6.
Environ Sci Technol Lett ; 9(9): 706-711, 2022 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-36118960

RESUMEN

Mobility reductions following the COVID-19 pandemic in the United States were higher, and sustained longer, for aviation than ground transportation activity. We evaluate changes in ultrafine particle (UFP, Dp < 100 nm, a marker of fuel-combustion emissions) concentrations at a site near Logan Airport (Boston, Massachusetts) in relation to mobility reductions. Several years of particle number concentration (PNC) data prepandemic [1/2017-9/2018] and during the state-of-emergency (SOE) phase of the pandemic [4/2020-6/2021] were analyzed to assess the emissions reduction impact on PNC, controlling for season and wind direction. Mean PNC was 48% lower during the first three months of the SOE than prepandemic, consistent with 74% lower flight activity and 39% (local)-51% (highway) lower traffic volume. Traffic volume and mean PNC for all wind directions returned to prepandemic levels by 6/2021; however, when the site was downwind from Logan Airport, PNC remained lower than prepandemic levels (by 23%), consistent with lower-than-normal flight activity (44% below prepandemic levels). Our study shows the effect of pandemic-related mobility changes on PNC in a near-airport community, and it distinguishes aviation-related and ground transportation source contributions.

7.
J Am Coll Radiol ; 15(5): 755-761, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29571644

RESUMEN

PURPOSE: The aim of this article is to describe the development and implementation of structured reporting of adnexal mass findings on pelvic ultrasound in a large integrated health care delivery system. METHODS: A structured reporting system that includes standardized terminology for describing adnexal masses on ultrasound was developed by a multidisciplinary team of radiologists, gynecologists, and gynecologic oncologists on the basis of literature review and internal data. The system uses a reporting template that requires radiologists to assign abnormal adnexal masses to one of five possible categories on the basis of standardized criteria: category 0, 1, 2, or 3 for masses <10 cm, to reflect increasing concern for malignancy, and category X for masses >10 cm. Unique predefined hashtags were linked to each category to enable electronic data extraction, and a hard stop feature was installed that prevents reports from being finalized without a category designation. In 2014, after a 3-month pilot study, large-scale implementation was supported by an educational campaign consisting of web-based conferences, e-mail announcements, and local presentations. Clinical management recommendations on the basis of category and other clinical factors were provided in a separate practice resource for clinicians. RESULTS: Analysis of adherence revealed that 93% of the approximately 12,000 reports describing abnormal adnexal masses in 2016 included category designations. Feedback from referring providers via an anonymous survey indicated high levels of satisfaction with reports. CONCLUSIONS: Multidisciplinary collaboration and leveraging of technology enabled large-scale implementation of structured reporting with high levels of adherence among radiologists and improved satisfaction among referring providers.


Asunto(s)
Enfermedades de los Anexos/diagnóstico por imagen , Sistemas de Información Radiológica/organización & administración , Ultrasonografía/métodos , California , Diagnóstico Diferencial , Femenino , Humanos , Proyectos de Investigación , Programas Informáticos , Encuestas y Cuestionarios , Terminología como Asunto
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