Efficiency and regional distribution of high frequency ventilation

Thesis (Ph.D.)--Harvard-Massachusetts Institute of Technology Division of Health Sciences and Technology Program in Medical Engineering and Medical Physics, 1983.MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE.Bibliography: leaves 120-122.by Jose Gabriel Venegas T.Ph.D

Ventilation Defect Formation in Healthy and Asthma Subjects Is Determined by Lung Inflation

Background: Imaging studies have demonstrated that ventilation during bronchoconstriction in subjects with asthma is patchy with large ventilation defective areas (Vdefs). Based on a theoretical model, we postulated that during bronchoconstriction, as smooth muscle force activation increases, a patchy distribution of ventilation should emerge, even in the presence of minimal heterogeneity the lung. We therefore theorized that in normal lungs, Vdefs should also emerge in regions of the lung with reduced expansion. Objective: We studied 12 healthy subjects to evaluate whether Vdefs formed during bronchoconstriction, and compared their Vdefs with those observed in 9 subjects with mild asthma. Methods: Spirometry, low frequency (0.15 Hz) lung elastance and resistance, and regional ventilation by intravenous $^{13}$NN-saline positron emission tomography were measured before and after a challenge with nebulized methacholine. Vdefs were defined as regions with elevated residual 13NN after a period of washout. The average location, ventilation, volume, and fractional gas content of the Vdefs, relative to those of the rest of the lung, were calculated for both groups. Results: Consistent with the predictions of the theoretical model, both healthy subjects and those with asthma developed Vdefs. These Vdefs tended to form in regions that, at baseline, had a lower degree of lung inflation and, in healthy subjects, tended to occur in more dependent locations than in subjects with asthma. Conclusion: The formation of Vdefs is determined by the state of inflation prior to bronchoconstriction

The psychological science accelerator’s COVID-19 rapid-response dataset

In response to the COVID-19 pandemic, the Psychological Science Accelerator coordinated three large-scale psychological studies to examine the effects of loss-gain framing, cognitive reappraisals, and autonomy framing manipulations on behavioral intentions and affective measures. The data collected (April to October 2020) included specific measures for each experimental study, a general questionnaire examining health prevention behaviors and COVID-19 experience, geographical and cultural context characterization, and demographic information for each participant. Each participant started the study with the same general questions and then was randomized to complete either one longer experiment or two shorter experiments. Data were provided by 73,223 participants with varying completion rates. Participants completed the survey from 111 geopolitical regions in 44 unique languages/dialects. The anonymized dataset described here is provided in both raw and processed formats to facilitate re-use and further analyses. The dataset offers secondary analytic opportunities to explore coping, framing, and self-determination across a diverse, global sample obtained at the onset of the COVID-19 pandemic, which can be merged with other time-sampled or geographic data

Omecamtiv mecarbil in chronic heart failure with reduced ejection fraction, GALACTIC‐HF: baseline characteristics and comparison with contemporary clinical trials

Aims: The safety and efficacy of the novel selective cardiac myosin activator, omecamtiv mecarbil, in patients with heart failure with reduced ejection fraction (HFrEF) is tested in the Global Approach to Lowering Adverse Cardiac outcomes Through Improving Contractility in Heart Failure (GALACTIC‐HF) trial. Here we describe the baseline characteristics of participants in GALACTIC‐HF and how these compare with other contemporary trials. Methods and Results: Adults with established HFrEF, New York Heart Association functional class (NYHA) ≥ II, EF ≤35%, elevated natriuretic peptides and either current hospitalization for HF or history of hospitalization/ emergency department visit for HF within a year were randomized to either placebo or omecamtiv mecarbil (pharmacokinetic‐guided dosing: 25, 37.5 or 50 mg bid). 8256 patients [male (79%), non‐white (22%), mean age 65 years] were enrolled with a mean EF 27%, ischemic etiology in 54%, NYHA II 53% and III/IV 47%, and median NT‐proBNP 1971 pg/mL. HF therapies at baseline were among the most effectively employed in contemporary HF trials. GALACTIC‐HF randomized patients representative of recent HF registries and trials with substantial numbers of patients also having characteristics understudied in previous trials including more from North America (n = 1386), enrolled as inpatients (n = 2084), systolic blood pressure < 100 mmHg (n = 1127), estimated glomerular filtration rate < 30 mL/min/1.73 m2 (n = 528), and treated with sacubitril‐valsartan at baseline (n = 1594). Conclusions: GALACTIC‐HF enrolled a well‐treated, high‐risk population from both inpatient and outpatient settings, which will provide a definitive evaluation of the efficacy and safety of this novel therapy, as well as informing its potential future implementation

The Psychological Science Accelerator’s COVID-19 rapid-response dataset

In response to the COVID-19 pandemic, the Psychological Science Accelerator coordinated three large-scale psychological studies to examine the effects of loss-gain framing, cognitive reappraisals, and autonomy framing manipulations on behavioral intentions and affective measures. The data collected (April to October 2020) included specific measures for each experimental study, a general questionnaire examining health prevention behaviors and COVID-19 experience, geographical and cultural context characterization, and demographic information for each participant. Each participant started the study with the same general questions and then was randomized to complete either one longer experiment or two shorter experiments. Data were provided by 73,223 participants with varying completion rates. Participants completed the survey from 111 geopolitical regions in 44 unique languages/dialects. The anonymized dataset described here is provided in both raw and processed formats to facilitate re-use and further analyses. The dataset offers secondary analytic opportunities to explore coping, framing, and self-determination across a diverse, global sample obtained at the onset of the COVID-19 pandemic, which can be merged with other time-sampled or geographic data

Ecuaciones prácticas para resolver ejercicios de tiro parabólico

There will be an easy solution for solving fundamental problems of free-flight motion of a projectile? This is a basic question from which this paper starts. In this research five equations were obtained, that simply solves Two-Dimensional problems of free-flight motion of a projectile under a constant downward acceleration. Air Viscous Friction is not taken into account. These equations are obtained from the constant acceleration equations. Five problems of free-flight motion of a projectile were solved using those equations vs Classical Theory. Results show that there is a variation between them of 0.237%, which demonstrates the effectiveness of the proposed method.Esta investigación surge de la pregunta si habrá una forma directa de resolver ejercicios de tiro parabólico, el cual es un tema básico, pero, a la vez, complejo en cursos introductorios de física. Por esta razón, es importante conocer, comprender y analizar este tipo de fenómenos físicos. En este trabajo se obtuvo un conjunto de ecuaciones para resolver ejercicios de tiro parabólico en dos dimensiones de forma directa, para casos donde se considera una aceleración gravitacional constante y se desprecia la fuerza de rozamiento del aire. Estas ecuaciones son deducidas algebraicamente a partir de las ecuaciones generales del movimiento rectilíneo uniforme y uniformemente acelerado. Cinco tipos de ejercicios de tiro parabólico fueron resueltos empleando el método presentado en este trabajo y los métodos clásicos. Los resultados obtenidos muestran que la variación de su magnitud en todos los casos es menor a 0.372%, lo que demuestra la aceptable efectividad de la propuesta presentada

Matemática Básica - MA420 - 202101

1 Este es un curso general que corresponde a la línea de matemática para las carreras de ingeniería, es de carácter teórico-práctico; está dirigido a los estudiantes de primer ciclo; proporciona el soporte matemático al estudiante para las asignaturas siguientes propias de cada especialidad, por tal razón los conceptos de cada tema se definen de forma sencilla, relacionándolos con problemas afines a la ingeniería. En este curso el alumno va a desarrollar la competencia general de razonamiento cuantitativo, en el nivel 1, a través de las dimensiones de: interpretación, representación, cálculo, análisis y comunicación o argumentación en problemas sencillos de contexto real. Al finalizar el curso el alumno será capaz de trabajar con datos alfanuméricos, representados de diferentes formas (tablas, gráficos, etc.) y utilizarlos como argumentos para sustentar una idea o tomar decisiones en base a esta información

Evaluation of the Use of Autonomous Reef Monitoring Structures (ARMS) for Describing the Species Diversity of Two Coral Reefs in the Yucatan Peninsula, Mexico

Autonomous reef monitoring structures (ARMS) have been proposed as a standardized, passive, nondestructive sampling tool. This study assessed the ability of ARMS to capture the cryptic species diversity of two coral reefs by recording species richness and taxonomic representativeness using conventional taxonomy. The capacity of ARMS, as artificial substrates, to favor the establishment of nonindigenous species over native species was also evaluated. The use of ARMS allowed the detection of 370 species morphotypes from nine phyla, yielding 13 new records of geographic distribution expansion, one exotic species for the Gulf of México and the Caribbean Sea, and six newly described species. It was also possible to make spatial comparisons of species richness between both reefs. ARMS captured cryptic diversity exceptionally well, with the exception of echinoderms. Furthermore, these artificial structures did not hinder the colonization ability of native species; in fact, the colonization patterns on the structures themselves represented the spatial differences in the structure of benthic assemblages. This study represents the first effort to make a conventional taxonomic description of the cryptic fauna of the Yucatan Peninsula using ARMS. It is recommended to assess coral reef species diversity, but more taxonomists specialized in marine invertebrates are needed