Nondiffractive sonic crystals

We predict theoretically the nondiffractive propagation of sonic waves in periodic acoustic media (sonic crystals), by expansion into a set of plane waves (Bloch mode expansion), and by finite difference time domain calculations of finite beams. We also give analytical evaluations of the parameters for nondiffractive propagation, as well as the minimum size of the nondiffractively propagating acoustic beams.Comment: 7 figures, submitted to J. Acoust. Soc. A

Correlation between objective and subjective assessment of noise barriers

There are several international standards that define the way to evaluate the attenuation capacity of noise reducing devices, by single-number quantities representing airborne sound insulation and insertion loss. These two single-value ratings define the quality and performance of acoustic barriers, the former being related to intrinsic and the latter to both intrinsic and extrinsic acoustic characteristics of the devices. However, not many studies can be found on whether these objective parameters correlate to the perception of annoyance reduction. The aim of the present work is to analyze the adequacy of these objective ratings to indicate the performance of noise barriers, by comparing their values with the perception of annoyance reduction. For this purpose, ninety individuals of two different nationalities (Spanish and Portuguese) were asked to rate the perceived annoyance reduction in a listening experimental test, in which they were exposed, under controlled conditions, to several environmental noises and acoustic screened stimuli simulated by audio filters. The obtained results show a high correlation between objective ratings and subjective annoyance perception, with a better correlation being observed for insertion loss single-number parameter than for the airborne sound insulation single-number rating. Furthermore, significant differences were found depending on the gender and nationality of the respondents. The results, from this ongoing research work, may be of great interest for future acoustic barriers design

¿Es mayor la mortalidad en los pacientes que han sufrido una fractura de cadera?

Introducción y objetivos El objetivo de este estudio es valorar si los pacientes que han sufrido una fractura de cadera tienen una mortalidad más alta de la esperada. Material y métodos Se realizó un estudio prospectivo, observacional donde se toma como muestra los pacientes con fractura de cadera a lo largo de un año, cuya cifra fue de 284 y el seguimiento mínimo fue de 2 años. La edad media de estos pacientes fue de 84, 26 años, siendo el 21, 48% (61/284) varones y el 78, 5% (223/284) mujeres. La supervivencia y las enfermedades previas que afectan a la mortalidad como factores de riesgo se recogieron y se analizaron mediante el método de Kaplan-Meier y mediante la regresión de Cox. Se comparó la mortalidad real con la esperada según el Índice de Comorbilidad de Charlson, ajustado por la edad. Resultados La patología previa fue el principal factor de mortalidad, siendo la cardiopatía la más significativa (HR: 1, 817; IC95%: 1, 048; 3, 149). La mortalidad real al año de la muestra fue del 22, 5%, mientras que la mortalidad anual estimada según el Índice de Comorbilidad de Charlson era de un 29, 68% (IC95%: 44, 36-15). Conclusiones La fractura de cadera no provoca un aumento de mortalidad según la estimación del Índice de Comorbilidad de Charlson. Background and objective The aim of this study is to value whether patients who have suffered a hip fracture have a higher mortality than expected. Material and methods A prospective, observational study was carried out where patients with hip fracture were collected as a sample over a year. The study included 284 patients and a minimum follow-up was 2 years. The mean age of these patients was 84.26 years, with 21.48% (61/284) males and 78.5% (223/284) females. Survival and previous diseases that affect mortality, as risk factors, were collected and analyzed using the Kaplan-Meier method and the Cox regression model. Actual mortality was compared with that expected according to the Charlson Comorbidity Index, adjusted for age. Results Previous pathology was the main mortality factor, with heart disease being the most significant (OR 1.817, CI95%: 1.048; 3.149). The real mortality at one year of the sample was 22.5%, while the estimated annual mortality according to the Charlson Comorbidity Index was 29.68% (CI95%:44, 36-15). Conclusions Hip fracture does not cause an increase in mortality according to the Charlson Comorbidity Index estimate

El imaginario en torno a la Sociología, la Metodología y el papel del sociólogo en la sociedad, en los estudiantes de grado

El presente trabajo continúa uno anterior que sistematiza algunas de las reflexiones sostenidas a lo largo de nuestra experiencia como docentes integrantes de una cátedra de Metodología de la Investigación de la Carrera de Sociología de la Universidad de Buenos Aires, en torno a las percepciones de los estudiantes sobre el mencionado espacio curricular y cómo éstas se encuentran asociadas a su perspectiva respecto de su futura inserción social como sociólogos. Algunos de los interrogantes considerados fueron los siguientes: ¿qué lugar ocupa la Sociología en la trayectoria educativa de los estudiantes en relación a su espectro de intereses?; ¿los antecedentes familiares de inserción en las Ciencias Sociales y/o Humanidades inciden en la perspectiva asignada a la Sociología y a la mirada sobre las posibles inserciones laborales de los alumnos?; ¿qué concepciones acerca de la Metodología son las prevalecientes entre los estudiantes?; ¿qué relación existe, si alguna, entre la Metodología de la investigación y la Sociología?; ¿en qué medida el tránsito por la formación de grado modela y modifica sus concepciones iniciales respecto a la Sociología?; ¿existe una relación entre el perfil del egresado planteado por la carrera y lo que los alumnos imaginan acerca de él?Encuentro realizado junto con las V Jornadas de Sociología de la UNLP.Facultad de Humanidades y Ciencias de la Educació

Factores de riesgo en fractura periprotésica femoral tras artroplastia sustitutiva primaria de rodilla

Introducción y objetivos Las fracturas periprotésicas tras artroplastia primaria de rodilla cobran gran importancia en nuestro medio debido tanto al aumento de su incidencia, como al reto que suponen para el cirujano. Múltiples factores se han asociado a su producción. El objetivo del estudio fue identificar los factores de riesgo que podían influir en la aparición de estas fracturas, cuáles de todos ellos son modificables y generar un modelo de predicción de probabilidad de las mismas en función de dichos factores. Material y método Estudio analítico, observacional, retrospectivo, no pareado, de 38 casos de fracturas periprotésicas femorales de rodilla y 80 controles con prótesis de rodilla. En total, fueron incluidos en el estudio 118 pacientes, 83 mujeres y 35 hombres con una edad media de 72, 49 años. Se recogieron datos sociodemográficos, antecedentes médicos y consumo de fármacos, así como los relativos a la cirugía. Se realizó un análisis uni- y bivariante de los factores determinantes de fractura, usando un modelo de regresión logística para evitar el sesgo de confusión. Resultados De todos los factores estudiados según el modelo de regresión logística, se obtuvo que el sexo femenino (OR = 7, 6), la demencia (OR = 5), la alteración motora/párkinson (OR = 19, 3) y el sobrecorte femoral anterior (OR = 8, 6) eran factores asociados al incremento de riesgo de este tipo de fracturas. Conclusiones Este trabajo permite concluir que hay factores de riesgo, como son el sexo femenino, la demencia y el párkinson, que aumentan la probabilidad de fractura periprotésica, que son inherentes al paciente y no son modificables. Sin embargo, existe algún otro totalmente modificable que puede evitarse siendo exigente y exhaustivo en la técnica quirúrgica, como es el sobrecorte femoral anterior. Introduction and objectives: Periprosthetic fractures after primary knee arthroplasty has great importance in our environment due to the increase in their incidence and to the challenge they pose to the surgeon. Multiple factors have been associated with its production. The objective of the study was to identify the risk factors that could influence the appearance of these fractures, which of them are all modifiable and generate a probability prediction model based on these factors. Material and methods: Analytical, observational, retrospective, unpaired study of 38 cases of periprosthetic femoral knee fractures and 80 controls with knee prostheses. In total, 118 patients, 83 women and 35 men with a mean age of 72.49 years were included in the study. Sociodemographic data, medical history and drug consumption were collected, as well as those related to surgery. A univariate and bivariate analysis of the fracture determining factors was performed, using a logistic regression model to avoid confusion bias. Results: Of all the factors studied according to the logistic regression model, it was obtained that female sex (OR = 7.6), dementia (OR = 5), motor/parkinson''s alteration (OR = 19.3) and femoral overcut Previous (OR = 8.6) were factors associated with the increased risk of this type of fractures. Conclusions: This work allows us to conclude that there are risk factors such as female sex, dementia and parkinson''s that increase the probability of periprosthetic fracture that are inherent to the patient and are not modifiable. However, there is any other totally modifiable that can be avoided by being demanding and thorough in the surgical technique, such as the anterior femoral overcut

Astrobiological field campaign to a volcanosedimentary mars analogue methane producing subsurface protected ecosystem: Imuruk Lake (Alaska)

Viking missions reported adverse conditions for life in Mars surface. High hydrogen signal obtained by Mars orbiters has increased the interest in subsurface prospection as putative protected Mars environment with life potential. Permafrost has attracted considerable interest from an astrobiological point of view due to the recently reported results from the Mars exploration rovers. Considerable studies have been developed on extreme ecosystems and permafrost in particular, to evaluate the possibility of life on Mars and to test specific automated life detection instruments for space missions. The biodiversity of permafrost located on the Bering Land Bridge National Preserve has been studied as an example of subsurface protected niche of astrobiological interest. Different conventional (enrichment and isolation) and molecular ecology techniques (cloning, fluorescence "in situ" probe hybridization, FISH) have been used for isolation and bacterial identificationThe expedition to Imuruk Lake was supported by Centro de Astrobiología-INTA (Spain). The laboratory experimental procedures were supported by Grant AYA 2010–20213 “Desarrollo de Tecnología para la identificación de vida de forma automática” from the Spanish Governmen

Lifestyle and comorbid conditions as risk factors for community-acquired pneumonia in outpatient adults (NEUMO-ES-RISK project)

Introduction: Information about community-acquired pneumonia (CAP) risk in primary care is limited. We assess different lifestyle and comorbid conditions as risk factors (RF) for CAP in adults in primary care. Methods: A retrospective-observational-controlled study was designed. Adult CAP cases diagnosed at primary care in Spain between 2009 and 2013 were retrieved using the National Surveillance System of Primary Care Data (BiFAP). Age-matched and sex-matched controls were selected by incidence density sampling (ratio 2:1). Associations are presented as percentages and OR. Binomial regression models were constructed to avoid bias effects. Results: 51 139 patients and 102 372 controls were compared. Mean age (SD) was 61.4 (19.9) years. RF more significantly linked to CAP were: HIV (OR [95% CI]: 5.21 [4.35 to 6.27]), chronic obstructive pulmonary disease (COPD) (2.97 [2.84 to 3.12]), asthma (2.16 [2.07,2.26]), smoking (1.96 [1.91 to 2.02]) and poor dental hygiene (1.45 [1.41 to 1.49]). Average prevalence of any RF was 82.2% in cases and 69.2% in controls (2.05 [2.00 to 2.10]). CAP rate increased with the accumulation of RF and age: risk associated with 1RF was 1.42 (1.37 to 1.47) in 18-60-year-old individuals vs 1.57 (1.49 to 1.66) in >60 years of age, with 2RF 1.88 (1.80 to 1.97) vs 2.35 (2.23, 2.48) and with >/= 3 RF 3.11 (2.95, 3.30) vs 4.34 (4.13 to 4.57). Discussion: Prevalence of RF in adult CAP in primary care is high. Main RFs associated are HIV, COPD, asthma, smoking and poor dental hygiene. Our risk stacking results could help clinicians identify patients at higher risk of pneumonia

Excess hospitalizations and mortality associated with seasonal influenza in Spain, 2008-2018

Influenza may trigger complications, particularly in at-risk groups, potentially leading to hospitalization or death. However, due to lack of routine testing, influenza cases are infrequently coded with influenza-specific diagnosis. Statistical models using influenza activity as an explanatory variable can be used to estimate annual hospitalizations and deaths associated with influenza. Our study aimed to estimate the clinical and economic burden of severe influenza in Spain, considering such models. The study comprised ten epidemic seasons (2008/2009-2017/2018) and used two approaches: (i) a direct method of estimating the seasonal influenza hospitalization, based on the number of National Health Service hospitalizations with influenza-specific International Classification of Diseases (ICD) codes (ICD-9: 487-488; ICD-10: J09-J11), as primary or secondary diagnosis; (ii) an indirect method of estimating excess hospitalizations and deaths using broader groups of ICD codes in time-series models, computed for six age groups and four groups of diagnoses: pneumonia or influenza (ICD-9: 480-488, 517.1; ICD-10: J09-J18), respiratory (ICD-9: 460-519; ICD-10: J00-J99), respiratory or cardiovascular (C&R, ICD-9: 390-459, 460-519; ICD-10: I00-I99, J00-J99), and all-cause. Means, excluding the H1N1pdm09 pandemic (2009/2010), are reported in this study. The mean number of hospitalizations with a diagnosis of influenza per season was 13,063, corresponding to 28.1 cases per 100,000 people. The mean direct annual cost of these hospitalizations was €45.7 million, of which 65.7% was generated by patients with comorbidities. Mean annual influenza-associated C&R hospitalizations were estimated at 34,894 (min: 16,546; max: 52,861), corresponding to 75.0 cases per 100,000 (95% confidence interval [CI]: 63.3-86.3) for all ages and 335.3 (95% CI: 293.2-377.5) in patients aged ≥ 65 years. We estimate 3.8 influenza-associated excess C&R hospitalizations for each hospitalization coded with an influenza-specific diagnosis in patients aged ≥ 65 years. The mean direct annual cost of the estimated excess C&R hospitalizations was €142.9 million for all ages and €115.9 million for patients aged ≥ 65 years. Mean annual influenza-associated all-cause mortality per 100,000 people was estimated at 27.7 for all ages. Results suggest a relevant under-detected burden of influenza mostly in the elderly population, but not neglectable in younger people. The online version contains supplementary material available at 10.1186/s12879-023-08015-3

Salivary epidermal growth factor correlates with hospitalization length in rotavirus infection

The IFI27 interferon gene expression has been found to be largely increased in rotavirus (RV)-infected patients. IFI27 gene encodes for a protein of unknown function, very recently linked to epidermal proliferation and related to the epidermal growth factor (EGF) protein. The EGF is a low-molecular-weight polypeptide that is mainly produced by submandibular and parotid glands, and it plays an important physiological role in the maintenance of oro-esophageal and gastric tissue integrity. Our aim was to determine salivary EGF levels in RV-infected patients in order to establish its potential relationship with IFI27 increased expression and EGF-mediated mucosal protection in RV infection. We conducted a prospective comparative study using saliva samples from 27 infants infected with RV (sampled at recruitment during hospital admission and at convalescence, i.e. at least 3 months after recovery) and from 36 healthy control children. Median (SD) EGF salivary concentration was 777 (529) pg/ml in RV-infected group at acute phase and 356 (242) pg/m at convalescence, while it was 337 (119) pg/ml in the healthy control group. A significant association was found between EGF levels and hospitalization length of stay (P-value = 0.022; r(2) = -0.63). The salivary levels of EGF are significantly increased during the acute phase of natural RV infection, and relate to length of hospitalization. Further assessment of this non-invasive biomarker in RV disease is warranted.Instituto de Salud Carlos IIIXunta de Galicia. Consellería de Sanidad