Performance based earthquake assessment of an industrial silos structure and retrofit with sliding isolators

Recent seismic events pointed out the high vulnerability of existing industrial facilities, stressing on safety and high losses inherent to interruption of economic activities and release of environmentally hazardous materials. These structures often have irregular geometry and structural configuration, are subject to aging and corrosion, and are designed without specific performance-based or seismic design criteria. Due to these inherent complexities, retrofit using friction isolators can be a viable and practical solution for performance improvements. This work presents a case study of irregular industrial storage plant structure consisting of a group of six elevated silos resting on a steel frame on one side and connected to a vaulted RC structure on the other. A computational model is built incorporating nonlinearities from the components (braces, beams, columns, etc.) and from the mitigation devices. Retrofit using friction isolators is analyzed and evaluated through linear and nonlinear dynamic analyses under a set of natural ground motions. Results show the effectiveness of the mitigation strategy in terms of performance improvement

Endothelial dysfunction in postmenopausal women and hypertension

‘Menopause is a cardiovascular risk factor for endothelial dysfunction … It also represents a unique opportunity to study the effect of endothelial dysfunction in healthy women and predicts the development of atherosclerosis and atherosclerosis-related diseas

Gender differences in diagnostic procedures

This review examines the contribution of the literature to the controversial issue of diagnostic procedures in women affected by coronary artery disease (CAD), on which a large number of papers have been published. It has been reported that cerebro- and cardiovascular diseases represent the first cause of death in the New as well as in the Old World, Italy included. Some studies are conditioned by bias; one of these is the Framingham study, in which angina was reported and defined only clinically and for a relatively young age range, as a benign condition in women. Angiographic studies, such as the CASS, considered a super elected group of women referred to the hemodynamic laboratory for chest pain, which in the female gender often has atypical characteristics. In our opinion, it is mandatory to take into account: 1) what chest pain really means in women; 2) the fact that there are gender differences: women have a different biological and hormonal status, lifestyle, and perception of the disease; 3) that there is a different approach of the physicians to a woman with possible or suspected CAD. We suggest, therefore, a more peculiar and individualized diagnostic approach to women suspected as having CAD. This approach should also take the pre-test probability of disease into consideration. The first investigational step we recommend is the exercise ECG test; should this be unfeasible or not interpretable, an imaging and/or pharmacological stress test is advisable. In case of positive first test results, coronary angiography should be performed. © 2003 CEPI Srl

Reactive oxygen species generated in chloroplasts contribute to tobacco leaf infection by the necrotrophic fungus Botrytis cinerea

Reactive oxygen species (ROS) play fundamental roles in plant responses to pathogen infection, including modulation of cell death processes and defense-related gene expression. Cell death triggered as part of the hypersensitive response enhances resistance to biotrophic pathogens, but favors the virulence of necrotrophs. Even though the involvement of ROS in the orchestration of defense responses is well established, the relative contribution of specific subcellular ROS sources to plant resistance against microorganisms with different pathogenesis strategies is not completely known. The aim of this work was to investigate the role of chloroplastic ROS in plant defense against a typical necrotrophic fungus, Botrytis cinerea. For this purpose, we used transgenic Nicotiana tabacum (tobacco) lines expressing a plastid-targeted cyanobacterial flavodoxin (pfld lines), which accumulate lower chloroplastic ROS in response to different stresses. Tissue damage and fungal growth were significantly reduced in infected leaves of pfld plants, as compared with infected wild-type (WT) counterparts. ROS build-up triggered by Botrytis infection and associated with chloroplasts was significantly decreased (70–80%) in pfld leaves relative to the wild type. Phytoalexin accumulation and expression of pathogenesis-related genes were induced to a lower degree in pfld plants than in WT siblings. The impact of fungal infection on photosynthetic activity was also lower in pfld leaves. The results indicate that chloroplast-generated ROS play a major role in lesion development during Botrytis infection. This work demonstrates that the modulation of chloroplastic ROS levels by the expression of a heterologous antioxidant protein can provide a significant degree of protection against a canonical necrotrophic fungus.Fil: Rossi, Franco Rubén. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas ; ArgentinaFil: Krapp, Adriana del Rosario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Bisaro, Fabiana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; Argentina. The Queens University of Belfast; IrlandaFil: Maiale, Santiago Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas ; ArgentinaFil: Pieckenstain, Fernando Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas ; ArgentinaFil: Carrillo, Nestor Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; Argentin

Impegno cardiaco nella sclerosi sistemica

L'impegno cardiaco in corso di sclerosi sistemia consta di uno spettro variabile di manifestazioni cliniche conseguenti ad alterazioni di natura microangiopatica, elettrica e/o emodinamica. In danno ischemico e/o flogistico autoimmune del miocardio producono, in ultima analisi, il quadro istopatologico caratteristico della 'necrosi a bande' con deposizione di tessuto fibroso, responsabile della riduzione di elasticità e della capacità contrattile muscolare. ...

The Isolation and Identification of Bacteria on Feathers of Migratory Bird Species

Worldwide, bacteria are the most ubiquitous microorganisms, and it has been extensively demonstrated that migratory wild birds can increase bacterial global scale dispersion through long-distance migration and dispersal. The microbial community hosted by wild birds can be highly diverse, including pathogenic strains that can contribute to infections and disease spread. This study focused on feather and plumage bacteria within bird microbial communities. Samples were collected during ornithological activities in a bird ringing station. Bacterial identification was carried out via DNA barcoding of the partial 16S rRNA gene. Thirty-seven isolates of bacteria were identified on the chest feathers of 60 migratory birds belonging to three trans-Saharan species: Muscicapa striata, Hippolais icterina, and Sylvia borin. Our results demonstrate the possibility of bacterial transfer, including pathogens, through bird migration between very distant countries. The data from the analysis of plumage bacteria can aid in the explanation of phenomena such as migratory birds’ fitness or the development of secondary sexual traits. Moreover, these results have deep hygienic–sanitary implications, since many bird species have synanthropic behaviors during their migration that increase the probability of disease sprea

Dynamic Model of a Conjugate-Surface Flexure Hinge Considering Impacts between Cylinders

A dynamic model of a Conjugate-Surface Flexure Hinge (CSFH) has been proposed as a component for MEMS/NEMS Technology-based devices with lumped compliance. However, impacts between the conjugate surfaces have not been studied yet and, therefore, this paper attempts to fill this gap by proposing a detailed multibody system (MBS) model that includes not only rigid-body dynamics but also elastic forces, friction, and impacts. Two models based on the Lankarani-Nikravesh constitutive law are first recalled and a new model based on the contact of cylinders is proposed. All three models are complemented by the friction model proposed by Ambrosio. Then, the non-smooth Moreau time-stepping scheme with Coulomb friction is described. The four models are compared in different scenarios and the results confirm that the proposed model outcomes comply with the most reliable models

Noninvasive evaluation of coronary artery stents patency after PTCA: role of Multislice Computed Tomography.

Restenosis of a coronary artery treated with stent implantation is a well-known process that can compromise over time the success of a coronary angioplasty and, accordingly, treated patients must undergo periodic controls. We have recently witnessed a shift towards a greater use of Multi-slice CT (msCT) in the study of coronary disease without its precise indications and limits having yet been underlined. The purpose of our study is to assess the role of msCT in the follow-up of patients treated with coronary angioplasty.Forty-eight patients, for a total of 72 lesions, who underwent treatment with a slotted tube stent implant, had an msCT examination 1 week before scheduled coronary angiography, and the results were compared. 34 stents/72 (47.2\%) were inserted on the left anterior descending; 21/72 (29.2\%) on the right coronary; 17/72 (23.6\%) on the circumflex artery or obtuse marginal branches.The observation of the opacification of the vessel located distally to treated segments allowed us to assess the patency of all stents. Coronary angiography identified a significant intrastent restenosis or a stent occlusion in 12 of the 72 stents analysed (16.7\%). msCT enabled easier visualization of the lumen of the treated artery and its differentiation from the stent struts in the ones located on the left anterior descending artery than those on the circumflex (28 stents out of 34 [82.4\%] vs 13/17 [76.5\%]; p3.5 mm (OR 2.97 [IC 95\%: from 1.67 to 4.86]; p<0.01).The msCT technology available at present makes the study of smaller stents and those positioned on the right coronary artery and circumflex rather complex; on the other hand msCT appears a promising study method for stents greater then 3.5 mm and for those positioned on the proximal segment of the left anterior descending artery

Acute myocardial infarction with occlusion of all three main epicardial coronary arteries: When Mother Nature takes care more than physicians

Double-arterial coronary stent thrombosis in acute myocardial infarction (AMI) is an infrequent but severe complication, especially when the third main coronary artery is chronically occluded. The conus artery (CA) can serve as a major source of collateral when the left anterior descendent coronary artery (LAD) becomes obstructed. We report a case of a 48-year-old man presenting with AMI due to a very late double-arterial stent thrombosis (ST) following drug-eluting stent implantation and a chronic occlusion of LAD collateralized by a large anomalous CA, which provided for the entire vascularization of the coronary tree. © 2010 Springer

Effects of antihypertensive treatment on endothelial function in postmenopausal hypertensive women. A significant role for aldosterone inhibition

Introduction: Endothelial dysfunction is a well-demonstrated independent predictor of cardiovascular events in hypertensive postmenopausal women. Accordingly, it is plausible that improving endothelial function could represent an adjunctive target for antihypertensive treatment. The aim of our study was to evaluate the effect of pharmacologic treatment on endothelial function in the specific population of hypertensive postmenopausal women.Methods: A total of 320 consecutive hypertensive postmenopausal women underwent a high-resolution ultrasound study of the brachial artery at baseline and after six months, while 'optimal' control of blood pressure (maintenance of blood pressure values below 140/90 mmHg at all follow-up visits) was achieved using antihypertensive therapy. Endothelial function was measured as flow-mediated dilation, using ultrasound method.Results: After six months of treatment, flow-mediated dilatation (FMD) had significantly improved in the majority of patients (n = 257 [80.3% of the entire population]; FMD = 8.1 ± 1.0% at baseline vs. 10.6 ± 1.5% after follow-up; p < 0.001), but it had not changed or worsened in others (n = 63 [19.7%]; FMD = 8.2 ± 1.2% at baseline vs. 7.6 ± 1.0% after six months; p = ns). Improvement of endothelial function, at multivariate analysis, resulted independently associated with the use of aldosterone inhibitors (odds ratio = 2.15; 95% confidence interval: 1.55-2.75; p = 0.001).Conclusions: This study demonstrates that a significant improvement in endothelial function may be obtained after six months of an optimal antihypertensive therapy. Among all hypertensive postmenopausal women that achieved an optimal control of blood pressure during follow-up, the use of drugs that inhibit aldosterone receptors was associated with an improvement of endothelial function, beyond the 'optimal' blood pressure control. © SAGE Publications 2011