We present a two-point model to investigate the underlying source mechanisms for broadband shock-associated noise (BBSAN) in shock-containing supersonic jets. In the model presented, the generation ...of BBSAN is assumed to arise from the nonlinear interaction between downstream-propagating coherent structures with the quasi-periodic shock cells in the jet plume. The turbulent perturbations are represented as axially extended wavepackets and the shock cells are modelled as a set of stationary waveguide modes. Unlike previous BBSAN models, the physical parameters describing the hydrodynamic components are not scaled using the acoustic field. Instead, the source characteristics of both the turbulent and shock components are extracted from the hydrodynamic region of large-eddy simulation and particle image velocimetry datasets. Apart from using extracted data, a reduced-order description of the wavepacket structure is obtained using parabolised stability equations. The validity of the model is tested by comparing far-field sound pressure level predictions to azimuthally decomposed experimental acoustic data from a cold Mach 1.5 underexpanded jet. At polar angles and frequencies where BBSAN dominates, encouraging comparisons of the radiated noise spectra for the first three azimuthal modes, in both frequency and amplitude (${\pm }2\ \textrm {dB}\,\textrm {St}^{-1}$ at peak frequency), reinforce the suitability of using reduced-order wavepacket sources for predicting BBSAN peaks. On the other hand, wavepacket jitter is found to have a critical role in recovering sound amplitude at interpeak frequencies. The paper presents a quantitative demonstration that the wavepacket–shock interaction, carefully reconstructed by extracting components from data or linearised models, contains the correct essential flow physics that accounts for most features of the far-field BBSAN spectra.
El artículo reflexiona en torno al impacto de la erupción del volcán Calbuco vivido por los habitantes de la comuna de Puerto Varas, Chile en el 2015. A partir de una investigación cualitativa de ...estudio de caso se indaga en la experiencia subjetiva de los afectados desde de los impactos en lo psicosocial y en salud mental de familias habitantes de Ensenada a 6 meses de la emergencia. El objetivo es describir y reflexionar sobre el estado que se encuentran las familias luego de haber vivido esta experiencia crítica, la cual instala una situación de anormalidad y se expresa en diversos estados de afectación. Se observa así impactos en lo psicosocial en el daño de sus viviendas, pérdida del lugar de trabajo y fuente de empleo, la alteración del paisaje, así como un estado de malestar colectivo siendo manifestado en el cuerpo, en estados emocionales y en relaciones sociales. Reflexión que permite concluir que la comunidad afectada sufrió tanto por los efectos de la expresión de la amenaza, así como por el abandono social producto de una gestión institucional cuyo foco estuvo en las pérdidas materiales y económicas y el restablecimiento de la normalidad sin considerar las particularidades territoriales.
Health-related quality of life (HRQOL) is an important goal of therapy for chronic myeloid leukemia (CML) patients treated with current molecular-targeted therapies. The main objective of this study ...was to investigate factors associated with long-term HRQOL outcomes of CML patients receiving imatinib. Analysis was performed on 422 CML patients recruited in an observational multicenter study. HRQOL was assessed with the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36). Key socio-demographic and clinical data were investigated for their association with HRQOL outcomes. Chronic fatigue and social support were also investigated. Univariate and multivariate linear regression analyses were used to identify independent factors associated with HRQOL outcomes. Fatigue was the only variable showing an independent and consistent association across all physical and mental HRQOL outcomes (P<0.01). Differences between patients reporting low versus high fatigue levels were more than eight and seven times the magnitude of a clinically meaningful difference, respectively, for the role physical (Δ=70 points) and emotional scale (Δ=63 points) of the SF-36. Fatigue did not occur as an isolated symptom and was most highly correlated with musculoskeletal pain (r=0.511; P≤0.001) and muscular cramps (r=0.448; P≤0.001). Chronic fatigue is the major factor limiting HRQOL of CML patients receiving imatinib.
OBJECTIVE:Drug utilization and clinical outcomes in hypertensive patients are suboptimal in different Countries, including Italy, leaving a large proportion of patients not at target blood pressure ...(BP).
DESIGN AND METHOD:We designed an observational study to define the number of patients diagnosed as hypertensive within the general adult population, the number of drugs prescribed to each patients and the number of hypertensive patients who were effectively treated. To this aim, clinical data collected by 150 General Practitioners (GPs) from 228.406 subjects living in the province of Verona (approximately 30% of the adult population) were analyzed after anonymization. Data retrieved from GPs official database concerned age, gender, number of antihypertensive agents prescribed at the same time over a period of 24 months, BP defined as categorical variable (cutoff 140/90 mmHg).
RESULTS:Data concerning the number of prescribed antihypertensive agents and BP control in relation to age are shown in the graph. A total of 43.526 subjects had a diagnosis of arterial hypertension (19% of the entire population, females 53%), 66% of them were aged 65 years or more and 86% received antihypertensive medications in the previous 2 years. The number of prescriptions increased with age. BP recordings were missing in 38% of cases. One third of all patients did not reach normal BP. Approximately 15% of patients could be considered as having resistant hypertension since requiring 4 drugs or not reaching normal BP with 3 drugs. Younger subjects (less than 65 years) more likely had BP not recorded (46%) and often received 1 or 2 antihypertensive agents, whether or not BP was controlled. Elderly patients (65 years or more) often required complex antihypertensive treatment (29% received 3–4 drugs) and their BP, in spite of a more stringent clinical follow up (66% had BP recorded), was uncontrolled in 48% of cases.(Figure is included in full-text article.)
CONCLUSIONS:BP control is not achieved in a large proportion of hypertensives, particularly the elderly patients although receiving a larger number of antihypertensive drugs. The present investigation helps to define the patients who may benefit from active monitoring and intervention aimed at improving the clinical outcomes.
OBJECTIVE:Type 1 diabetes mellitus (T1DM) is associated with early development of atherosclerosis. The aim of this study was to measure some indices of vascular damage in a group of children and ...adolescents with T1DM and their relationship with haemodynamic and metabolic parameters.
DESIGN AND METHOD:In a cross-sectional study, peripheral (pSBP/pDBP) and central systolic and diastolic blood pressure (cSBP/cDPB), carotid intima media thickness (cIMT) and carotid distensibility (cDC), pulse wave velocity (PWV) were measured using ultrasound and the SphygmoCor XCel device. Metabolic parameters, including triglycerides, LDL and HDL-cholesterol, were measured and glycated haemoglobin (HbA1c; average of the last two years) was calculated.
RESULTS:126 subjects with T1DM (61 females and 65 males, mean age 15.9 ± 2.6 years) followed at the Paediatric Diabetology Unit of Verona were evaluated at the Vascular Laboratory of the General Medicine & Hypertension Unit. Eighteen per cent of the sample had cDC under the 5th percentiles and 60% had cIMT higher than the 95th percentiles per sex and height. Both cSBP and pSBP were positively correlated with BMI (respectively r = 0.404; p < 0.0001 and r = 0.279; p < 0.01). A significant correlation between cSBP and all the measures of vascular damage was foundcDC (r = −0.410; p < 0.0001), PWV (r = 0.447; p < 0.0001), cIMT (r = 0.227; p < 0.01). The duration of diabetes, LDL-cholesterol and the average HbA1c were not correlated to any vascular phenotype. In linear regression analysis, after adjustment for all metabolic and anthropometric parameters, central SBP remained independently associated with subclinical carotid damage (for cIMT β = 0.002; p = 0.023; for cDC β = −0.343; p = 0.003) and PWV (β = 0.025; p < 0.001) whereas LDL-cholesterol with cIMT (β = 0.001; p < 0.05) and PWV (β = 0.025; p < 0.01).
CONCLUSIONS:Subclinical vascular damages are present in a high proportion of children and adolescents with T1DM. cSBP, more than pBP, is independently associated with indexes of vascular subclinical atherosclerosis, suggesting a pivotal role of blood pressure homeostasis, along with LDL-cholesterol, in determining vascular damage even during childhood and adolescence in patients with T1DM.
OBJECTIVE:We aimed at investigating the influence of weight excess and traditional cardiovascular risk factors on vascular structure and function in a sample of obese children.
DESIGN AND ...METHOD:Overweight or obese children (BMI > 90th percentile for sex and age) included in this observational study underwent office and ambulatory BP measurements (ABPM) and the assessment of carotid intima-media thickness (cIMT), endothelial function by the Flow Mediated Dilation (FMD) technique, carotid distensibility (cDC) by ultrasounds and stiffness index (SI) by digital photopletismography.
RESULTS:Sixty-six obese and 4 overweight children were enrolled (age 11.5 ± 2.4 years; female n30). Carotid IMT directly correlated with 24h- and nighttime SBP; cDC showed inverse correlations with BMI and waist circumference and 24h-BP. Unexpectedly, SI resulted inversely related with several indexes of weight excess. Most of these correlations remained significant after adjustment for age, sex, BMI and BP. In a replication set of 40 obese children SI, but not Pulse Wave Velocity (PWV), was still inversely associated with BMI.
CONCLUSIONS:These data suggest that arterial structure and elasticity are negatively affected by weight excess and BP levels, even in childhood. Surprisingly, SI might not be a reliable marker of vascular stiffness in obese children, because this measure is probably confounded by other factors including vasodilation.
Adrenal incidentalomas, defined as masses discovered incidentally during imaging investigation of non-adrenal disorders, have become a rather common finding in clinical practice. The prevalence is ...not well characterized and varies among studies. The aim of the present study was to perform a prospective evaluation of the prevalence of adrenal incidentalomas among subjects undergoing computerized tomography (CT) scan of the chest in a screening program of lung cancer (Tic TAC study) in Piedmont, a region of Northwestern Italy. This evaluation included 520 subjects (382 males and 138 females, aged between 55-82 yr), referred to our hospital from April to December 2001. Twenty-three patients with adrenal masses were identified: 21 adrenal adenomas, 1 myelolipoma, and 1 metastasis of lung cancer. Therefore, the overall prevalence of adrenal lesions was 4.4%, and that of benign adrenal masses was 4.2%. This prevalence is higher than those found in previous CT scan series reported in the literature, probably because of the use of high-resolution CT scanning technology. Another factor that influenced our results is that subject age is skewed towards the decades characterized by a greater occurrence of adrenal masses. The outcome of this study confirms that we are presently able to identify incidentally discovered adrenal masses more often than in early years and that the prevalence of adrenal incidentalomas on CT images is approaching that of autopsy series. The present study provides a reliable estimate of the prevalence of adrenal incidentaloma with currently used CT scanners. Notwithstanding that our subjects were at increased risk of lung cancer, the rate of adrenal metastases was low. We think that the present results can be generalized even if we may disclose the lack of histological diagnosis.
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