Fotometría infrarroja

Se presentan aquí los resultados obtenidos por intermedio de un programa de observaciones fotométricas sobre estrellas tipo Mira y Be, en las bandas JKL del infrarrojo cercano. Las observaciones fueron realizadas con el fotómetro infrarrojo del OALP, bajo la dirección del Dr. Alejandro Feinstein.Asociación Argentina de Astronomí

Pequeñas historias de humor y de horror : usando narrativas y casos en la formación del profesorado de ciencias

En este trabajo se discute el uso de “pequeñas historias” en la formación inicial y continuada del profesorado de ciencias para todos los niveles educativos. Se presenta un proyecto de investigación e innovación didácticas dirigido a fomentar, en profesores y profesoras de ciencias, algunos procesos cognitivolingüísticos epitómicos (paradigmáticos) de las ciencias. Para tal proyecto se diseñaron dos relatos cortos basados en materiales de historia de la ciencia. Los relatos asumen un formato narrativo y se utilizan como casos de estudio; en ellos se recurre al humor y al horror como herramientas de estructuración del hilo argumental. El contenido y el formato de los relatos tiene su base en investigaciones previas acerca de la naturaleza de la ciencia; estas “pequeñas historias” pretendían construir una imagen más robusta de la ciencia como actividad profundamente humana

A New Approach for the Relative Surface Free Energy of Cubic Material with Terrace, Step, and Kink Structures

A new relationship between the relative surface free energy and the surface structure of a cubic material with terrace, step, and kink structures based upon the application of the information theory is presented. Any surface of a face centered cubic crystal exists as combinations of (111), (100), and (110) microfacets with a certain concentration of kinks, corners, and border of terraces. By use of the most dense atomic array, the entire crystallographic surface can be described, including the corresponding relative surface free energy of each kind of site. The results can be correlated with existing experimental data.Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicada

Utilization of Intensive Care Unit Nutrition Consultation Is Associated With Reduced Mortality

BackgroundThe aim of this project was to investigate the prevalence of nutrition consultation (NC) in U.S. intensive care units (ICUs) and to examine its association with patient outcomes.MethodsData from the Healthcare Cost and Utilization Project’s state inpatient databases was utilized from 2010 â 2014. A multilevel logistic regression model was used to evaluate the relationship between NC and clinical outcomes.ResultsInstitutional ICU NC rates varied significantly (mean: 14%, range: 0.1%â 73%). Significant variation among underlying disease processes was identified, with burn patients having the highest consult rate (P < 0.001, mean: 6%, range: 2%â 25%). ICU patients who received NC had significantly lower inâ hospital mortality (odds ratio [OR] 0.59, 95% confidence interval [CI] 0.48â 0.74, P < 0.001), as did the subset with malnutrition (OR 0.72, 95% CI 0.53â 0.99, P = 0.047) and the subset with concomitant physical therapy consultation (OR 0.53, 95% CI 0.38â 0.74, P < 0.001). NC was associated with significantly lower rates of intubation, pulmonary failure, pneumonia, and gastrointestinal bleeding (P < 0.05). Furthermore, patients who received NC were more likely to receive enteral or parenteral nutrition (ENPN) (OR 1.8, 95% CI 1.4â 2.3, P < 0.001). Patients who received followâ up NC were even more likely to receive ENPN (OR 3.0, 95% CI 2.1â 4.2, P < 0.001).ConclusionsRates of NC were low in critically ill patients. This study suggests that increased utilization of NC in critically ill patients may be associated with improved clinical outcomes.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154413/1/jpen1534_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154413/2/jpen1534.pd

Efficacy of Losartan in Hospitalized Patients With COVID-19-Induced Lung Injury: A Randomized Clinical Trial

Importance: SARS-CoV-2 viral entry may disrupt angiotensin II (AII) homeostasis, contributing to COVID-19 induced lung injury. AII type 1 receptor blockade mitigates lung injury in preclinical models, although data in humans with COVID-19 remain mixed. Objective: To test the efficacy of losartan to reduce lung injury in hospitalized patients with COVID-19. Design, Setting, and Participants: This blinded, placebo-controlled randomized clinical trial was conducted in 13 hospitals in the United States from April 2020 to February 2021. Hospitalized patients with COVID-19 and a respiratory sequential organ failure assessment score of at least 1 and not already using a renin-angiotensin-aldosterone system (RAAS) inhibitor were eligible for participation. Data were analyzed from April 19 to August 24, 2021. Interventions: Losartan 50 mg orally twice daily vs equivalent placebo for 10 days or until hospital discharge. Main Outcomes and Measures: The primary outcome was the imputed arterial partial pressure of oxygen to fraction of inspired oxygen (Pao2:Fio2) ratio at 7 days. Secondary outcomes included ordinal COVID-19 severity; days without supplemental o2, ventilation, or vasopressors; and mortality. Losartan pharmacokinetics and RAAS components (AII, angiotensin-[1-7] and angiotensin-converting enzymes 1 and 2)] were measured in a subgroup of participants. Results: A total of 205 participants (mean [SD] age, 55.2 [15.7] years; 123 [60.0%] men) were randomized, with 101 participants assigned to losartan and 104 participants assigned to placebo. Compared with placebo, losartan did not significantly affect Pao2:Fio2 ratio at 7 days (difference, -24.8 [95%, -55.6 to 6.1]; P = .12). Compared with placebo, losartan did not improve any secondary clinical outcomes and led to fewer vasopressor-free days than placebo (median [IQR], 9.4 [9.1-9.8] vasopressor-free days vs 8.7 [8.2-9.3] vasopressor-free days). Conclusions and Relevance: This randomized clinical trial found that initiation of orally administered losartan to hospitalized patients with COVID-19 and acute lung injury did not improve Pao2:Fio2 ratio at 7 days. These data may have implications for ongoing clinical trials. Trial Registration: ClinicalTrials.gov Identifier: NCT04312009

Vaccination Against SARS-CoV-2 Is Associated With a Lower Viral Load and Likelihood of Systemic Symptoms

Background: Data conflict on whether vaccination decreases severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral load. The objective of this analysis was to compare baseline viral load and symptoms between vaccinated and unvaccinated adults enrolled in a randomized trial of outpatient coronavirus disease 2019 (COVID-19) treatment. Methods: Baseline data from the first 433 sequential participants enrolling into the COVID-OUT trial were analyzed. Adults aged 30-85 with a body mass index (BMI) ≥25 kg/m2 were eligible within 3 days of a positive SARS-CoV-2 test and <7 days of symptoms. Log10 polymerase chain reaction viral loads were normalized to human RNase P by vaccination status, by time from vaccination, and by symptoms. Results: Two hundred seventy-four participants with known vaccination status contributed optional nasal swabs for viral load measurement: median age, 46 years; median (interquartile range) BMI 31.2 (27.4-36.4) kg/m2. Overall, 159 (58%) were women, and 217 (80%) were White. The mean relative log10 viral load for those vaccinated <6 months from the date of enrollment was 0.11 (95% CI, -0.48 to 0.71), which was significantly lower than the unvaccinated group (P = .01). Those vaccinated ≥6 months before enrollment did not differ from the unvaccinated with respect to viral load (mean, 0.99; 95% CI, -0.41 to 2.40; P = .85). The vaccinated group had fewer moderate/severe symptoms of subjective fever, chills, myalgias, nausea, and diarrhea (all P < .05). Conclusions: These data suggest that vaccination within 6 months of infection is associated with a lower viral load, and vaccination was associated with a lower likelihood of having systemic symptoms

Pequeñas historias de humor y de horror : usando narrativas y casos en la formación del profesorado de ciencias

En este trabajo se discute el uso de "pequeñas historias" en la formación inicial y continuada del profesorado de ciencias para todos los niveles educativos. Se presenta un proyecto de investigación e innovación didácticas dirigido a fomentar, en profesores y profesoras de ciencias, algunos procesos cognitivolingüísticos epitómicos (paradigmáticos) de las ciencias. Para tal proyecto se diseñaron dos relatos cortos basados en materiales de historia de la ciencia. Los relatos asumen un formato narrativo y se utilizan como casos de estudio; en ellos se recurre al humor y al horror como herramientas de estructuración del hilo argumental. El contenido y el formato de los relatos tiene su base en investigaciones previas acerca de la naturaleza de la ciencia; estas "pequeñas historias" pretendían construir una imagen más robusta de la ciencia como actividad profundamente humana