Hygrothermal performance of historic massive wall: when is 2D simulation necessary?

Hygrothermal analysis of historical building envelopes is crucial in ensuring their durability and enhancing their performances. The use of hygrothermal dynamic simulation is the most effective approach to predict moisture related damages or risk of mould growth on ancient masonry envelopes. However, simulating the hygrothermal behaviour of a historic wall composed by stones or bricks and mortar joints, with a detailed two-dimensional (2D) model, is typically a complex and time-consuming process. For this reason, in numerical models, composite walls are often simplified with a one-dimensional (1D) layer, neglecting the mortar joints. An oversimplified numerical model could affect the evaluation of a retrofit intervention and lead to inadequate design choices. This study evaluates when the description of a historic wall as a 1D homogenous layer leads to an acceptable level of accuracy and when it is necessary the use of a more precise 2D model. We quantified the error by comparing 1D and 2D simulations of different massive walls in three Italian climate conditions. We examined a possible retrofit intervention with different internal insulation systems considering vapor tight, vapor retardant and capillary active solutions. Although simplified 1D models are reliable for thermal parameters, we have identified a different behavior regarding the hygric parameters. Whereas for a capillary active insulation system the 1D and 2D simulations show a reasonable agreement, the 1D approximation is no longer acceptable in the case of vapour closed insulation systems as it leads to large deviations. Knowing when it is possible to implement a simplified 1D model and quantifying the introduced error will support architects and energy consultants in the design process. It will guide them in the choice of the most suitable model depending on their specific requirements

Applied Research of the Hygrothermal Behaviour of an Internally Insulated Historic Wall without Vapour Barrier: In Situ Measurements and Dynamic Simulations

The hygrothermal behaviour of an internally insulated historic wall is still hard to predict, mainly because the physical characteristics of the materials composing the historic wall are unknown. In this study, the hygrothermal assessment of an internally thermal insulated masonry wall of an historic palace located in Ferrara, in Italy, is shown. In situ non-destructive monitoring method is combined with a hygrothermal simulation tool, aiming to better analyse and discuss future refurbishment scenarios. In this context, the original U-value of the wall (not refurbished) is decreased from 1.44 W/m2K to 0.26 W/m2K (10 cm stone wool). Under the site specific conditions of this wall, not reached by the sun or rain, it was verified that even in the absence of vapour barrier, no frost damage is likely to occur and the condensation risk is very limited. Authors proposed further discussion based on simulation. The results showed that the introduction of a second gypsum board to the studied technology compensated such absence, while the reduction of the insulation material thickness provides a reduction of RH peaks in the interstitial area by 1%; this second solution proved to be more efficient, providing a 3% RH reduction and the avoidance of further thermal losses

Applied Research of the Hygrothermal Behaviour of an Internally Insulated Historic Wall without Vapour Barrier: In Situ Measurements and Dynamic Simulations

The hygrothermal behaviour of an internally insulated historic wall is still hard to predict, mainly because the physical characteristics of the materials composing the historic wall are unknown. In this study, the hygrothermal assessment of an internally thermal insulated masonry wall of an historic palace located in Ferrara, in Italy, is shown. In situ non-destructive monitoring method is combined with a hygrothermal simulation tool, aiming to better analyse and discuss future refurbishment scenarios. In this context, the original U-value of the wall (not refurbished) is decreased from 1.44 W/m2K to 0.26 W/m2K (10 cm stone wool). Under the site specific conditions of this wall, not reached by the sun or rain, it was verified that even in the absence of vapour barrier, no frost damage is likely to occur and the condensation risk is very limited. Authors proposed further discussion based on simulation. The results showed that the introduction of a second gypsum board to the studied technology compensated such absence, while the reduction of the insulation material thickness provides a reduction of RH peaks in the interstitial area by 1%; this second solution proved to be more efficient, providing a 3% RH reduction and the avoidance of further thermal losses

Ocular sarcoidosis : clinical experience and recent pathogenetic and therapeutic advancements

Purpose To describe the ocular manifestations in a cohort of patients with systemic sarcoidosis (SS). Recent advances in the pathophysiology, diagnosis, and therapy of SS are also discussed. Methods Data from 115 Italian patients diagnosed between 2005 and 2016 were retrospectively reviewed. All but the first 17 patients underwent a comprehensive ophthalmologic examination. The diagnosis was based on clinical features, the demonstration of non-caseating granulomas in biopsies from involved organs, and multiple imaging techniques. Data on broncho-alveolar lavage fluid analysis, calcemia, calciuria, serum angiotensin-converting enzyme levels and soluble interleukin-2 receptor levels were retrieved when available. Results Ocular involvement, detected in 33 patients (28.7%), was bilateral in 29 (87.9%) and the presenting feature in 13 (39.4%). Anterior uveitis was diagnosed in 12 patients (36.4%), Lofgren syndrome and uveoparotid fever in one patient each (3%), intermediate uveitis in 3 patients (9.1%), posterior uveitis in 7 (21.2%), and panuveitis in 9 (27.3%). First-line therapy consisted of corticosteroids, administered as eyedrops (10 patients), sub-Tenon's injections (1 patient), intravitreal implants (9 patients), or systemically (23 patients). Second-line therapy consisted of steroid-sparing immunosuppressants, including methotrexate (10 patients) and azathioprine (10 patients). Based on pathogenetic indications that tumor necrosis factor (TNF)-alpha is a central mediator of granuloma formation, adalimumab, targeting TNF-alpha, was employed in 6 patients as a third-line agent for severe/refractory chronic sarcoidosis. Conclusion Uveitis of protean type, onset, duration, and course remains the most frequent ocular manifestation of SS. Diagnostic and therapeutic advancements have remarkably improved the overall visual prognosis. An ophthalmologist should be a constant component in the multidisciplinary approach to the treatment of this often challenging but intriguing disease.Peer reviewe

Cardiovascular Hypertension-Mediated Organ Damage in Hypertensive Urgencies and Hypertensive Outpatients

BACKGROUND: The prevalence of hypertension mediated organ damage (HMOD) in patients attending the Emergency Department (ED) with symptomatic blood pressure (BP) rise is unknown, and whether HMOD varies between asymptomatic and symptomatic patients with grade 3 hypertension is unclear. AIM: This study aimed to investigate cardiac and vascular HMOD in hypertensive urgencies (HU) and asymptomatic outpatients with grade 1–3 hypertension. METHODS: Patients attending the ED with a symptomatic BP rise ≥180/110 mmHg were prospectively enrolled (HU group), after the exclusion of acute organ damage. HMOD and BP were assessed after 72 h from ED discharge in an office setting. These patients were matched by age and sex to outpatients with grade 3 hypertension (Grade 3 group), and by age, sex, and 72 h office BP values to outpatients with any grade hypertension (Control group). RESULTS: A total of 304 patients were enrolled (76 patients in the HU group, 76 in the Grade 3 group, and 152 in the Control group). Grade 3 patients had increased left ventricular mass (LVMi) compared to patients with HU (106.9 ± 31.5 vs. 96.1 ± 30.7 g/m(2), p = 0.035). Severe left ventricular hypertrophy (LVH) was more frequent in grade 3 (21.1 vs. 5.3%, p = 0.004), and pulse wave velocity (PWV) was similar in the two groups. There was no difference in LVMi between ED and Control patients (96.1 ± 30.7 vs. 95.2 ± 26.6 g/m(2), p = 0.807). LVH prevalence was similar (43.4 vs. 35.5%, p = 0.209, respectively), but patients with HU had thicker interventricular septum (11.9 ± 2.2 vs. 11.1 ± 2.2 mm, p = 0.007). PWV was similar between these two groups. Patients with HU needed more antihypertensive drugs than Control patients (2 vs. 1, p < 0.001). CONCLUSIONS: Patients with HU had a better cardiac HMOD profile than outpatients with grade 3 hypertension. Their cardiac and vascular HMOD is more comparable to an outpatient with similar in-office BP, although they need more antihypertensive medications

Ipertensione arteriosa e dilatazione dell'aorta toracica: un mistero insoluto

Summary Introduction Acute and chronic aortic syndromes are associated with substantial morbidity and mortality. Silent risk factors such as arterial hypertension and aortic root dilatation can increase the likelihood of aortic dissection or rupture. The relationship between arterial hypertension and the dimensions of the aortic root dimension is a topic of active debate. Materials and methods We reviewed the literature on the physiopathology, diagnosis, natural history, and management of thoracic aortic aneurysms. Results Biological variables influencing the size of the aorta include age, sex, body surface area, pressure values, and stroke volume. Pathologic enlargement of the thoracic aorta can be caused by genetic, degenerative, inflammatory, traumatic, or toxic factors. Studies investigating the correlation between aortic dimensions and arterial pressures (diastolic, systolic, or pulse) have produced discordant results. Discussion Classically, emphasis has been placed on the importance of hypertension-related degeneration of the medial layer of the aortic wall, which leads to dilatation of the thoracic aorta, reduced aortic wall compliance, and increased pulse pressures. However, there are no published data that demonstrate unequivocally the existence of a pathogenetic correlation between arterial hypertension and aortic root dilatation. Furthermore, there is no evidence that antihypertensive therapy is effective in the management of nonsyndromic forms of aortic root dilatation. An interesting branch of research focuses on the importance of genetic predisposition in the pathogenesis of thoracic aortic aneurysms. Different genetic backgrounds could explain differences in the behaviour of aortic walls exposed to the same hemodynamic stress. Further study is needed to evaluate these focal physiopathological aspects

Tavola rotonda “Le declinazioni della formazione nella sicurezza organizzata”

Convegno "La cultura della sicurezza fra organizzazione e formazione" Bari 20 novembre 2015 Tavola rotonda: “Le declinazioni della formazione nella sicurezza organizzata