Acoustic characteristics evaluation of an innovative metamaterial obtained through 3D printing technique

The reduction of interior noise level in the transportation sector is a big problem to cope with in view to increase the comfort of passengers. For this reason a great emphasis from the research community is devoted to develop new technology which are able to satisfy the mechanical requirements with concrete benefits from the acoustic point of view. Currently, it does not exist a solution for wideband range of frequency. Indeed, porous materials are characterized by outstanding dissipation in the high frequency range but they exhibit poor performance in the low and medium frequency range, where instead resonant cavities systems have the best performances but with narrow-band sound absorption. For this reason, the design and development of new materials which offers a good acoustic absorption over a wide range of frequencies is requested. In this paper, a hybrid metamaterial is designed, by coupling resonant cavities with micro-porous material and obtained through additive manufacturing technique which enables to model complex geometries that could not be feasible with classical manufacturing. Numerical and experimental studies have been conducted on the manufactured samples of PLA, with an interesting focus on the effect of each parameter which affects the absorption properties

Felodipine-metoprolol combination tablet: A valuable option to initiate antihypertensive therapy?

The aim of the present study was to assess the efficacy and tolerability of a calcium antagonist/β-blocker fixed combination tablet used as first-line antihypertesnive therapy in comparison with an angiotensin converting enzyme inhibitor and placebo. Patients with uncomplicated essential hypertension (diastolic blood pressure between 95 and 110 mm Hg at the end of a 4-week run-in period) were randomly allocated to a double-blind, 12-week treatment with either a combination tablet of felodipine and metoprolol (Logimax), 5/50 mg daily (n = 321), enalapril, 10 mg daily (n = 321), or placebo (n = 304), with the possibility of doubling the dose after 4 or 8 weeks of treatment if needed (diastolic blood pressure remaining >90 mm Hg). The combined felodipine-metoprolol treatment controlled blood pressure (diastolic ≤90 mm Hg 24 h after dose) in 72% of patients after 12 weeks, as compared with 49% for enalapril and 30% for placebo. A dose adjustment was required in 38% of patients receiving the combination, in 63% of patients allocated to placebo, and 61% of enalapril-treated patients. The overall incidence of adverse events was 54.5% during felodipine-metoprolol treatment; the corresponding values for enalapril and placebo were 51.7% and 47.4%, respectively. Withdrawal of treatment due to adverse events occurred in 18 patients treated with the combination, in 10 patients on enalapril, and 12 patients on placebo. No significant change in patients' well-being was observed in either of the three study groups. These results show that a fixed combination tablet of felodipine and metoprolol allows to normalize blood pressure in a substantially larger fraction of patients than enalapril given alone. This improved efficacy is obtained without impairing the tolerability. The fixed-dose combination of felodipine and metoprolol, therefore, may become a valuable option to initiate antihypertensive treatment. Am J Hypertens 1999;12:915-920 © 1999 American Journal of Hypertension, Lt

Reversal of Hartmann's procedure through the stomal side: A new even more minimal invasive technique

Background: Several minimal invasive, mainly laparoscopic-assisted, techniques for reversal of Hartmann's procedure (HP) have been published. The purpose of this pilot study was to assess a minimal invasive procedure through the stomal site that may compare favorably with open or laparoscopic-assisted procedures in terms of operative time, hospital stay and postoperative complications. Methods: HP reversal through the stomal side was attempted in 13 consecutive patients. Lysis of intra-abdominal adhesions was done manually through an incision at the formal stoma side, without direct vision between thumb and index finger. The rectal stump was identified intra-abdominally using a transanal rigid club. A manually controlled stapled end-to-end colorectal anastomosis was created. Results: Mean duration of operation was 81 min (range 58-109 min); mean hospital stay was 4.2 days (range 2-7 days). In two patients the procedure was converted because of strong adhesions in the lower pelvic cavity around the rectal stump that could not be lysed manually safely. No complications occurred in the patients in whom reversal was completely done through the stomal site. Conclusions: In our opinion, restoration of intestinal continuity through the stomal side after HP is a feasible operation, without need for additional incisions. In the hands of a specialist gastrointestinal surgeon this technique can be attempted in all patients, as conversion to a laparoscopic-assisted or an open procedure can be performed when necessary

Transnational strategy on the sustainable management and responsible use of non-native trees in the Alpine Space

Abstract Non-native tree species – defined as those species intentionally or unintentionally introduced by humans – have long been a part of the Alpine Space, providing numerous benefits, but also posing a potential threat to native biodiversity and related ecosystem services. Compared to the urban space where non-native trees comprise most tree species, the number of non-native trees in forests and plantations is relatively low. To evaluate potential risks and benefits of non-native trees in the Alpine Space, a transnational strategy for the responsible use and management of non-native trees is needed. The goals of the strategy are to tailor management practices for a sustainable and responsible use or admixture of non-native trees, to reduce the risks connected with the invasive potential of some non-native tree species, to help forests and urban areas to adapt to climate change, and to improve coordination and cooperation regarding best practices between different regions of the Alpine Space. A proposal was developed in a four-step process including expert-based assessment, stakeholder mapping, an extensive data review, and a public consultation. For implementing the strategy fully, strong collaboration among diverse stakeholders is anticipated and robust governance and an adequate long-term and fair funding scheme is needed

Iron age genomic data from Althiburos – Tunisia renew the debate on the origins of African taurine cattle

The Maghreb is a key region for understanding the dynamics of cattle dispersal and admixture with local aurochs following their earliest domestication in the Fertile Crescent more than 10,000 years ago. Here, we present data on autosomal genomes and mitogenomes obtained for four archaeological specimens of Iron Age (∼2,800 cal BP–2,000 cal BP) domestic cattle from the Eastern Maghreb, i.e. Althiburos (El Kef, Tunisia). D-loop sequences were obtained for an additional eight cattle specimens from this site. Maternal lineages were assigned to the elusive R and ubiquitous African-T1 haplogroups found in two and ten Althiburos specimens, respectively. Our results can be explained by post-domestication hybridization of Althiburos cattle with local aurochs. However, we cannot rule out an independent domestication in North Africa considering the shared ancestry of Althiburos cattle with the pre-domestic Moroccan aurochs and present-day African taurine cattle.info:eu-repo/semantics/publishedVersio

The complex TIE between macrophages and angiogenesis

Macrophages are primarily known as phagocytic immune cells, but they also play a role in diverse processes, such as morphogenesis, homeostasis and regeneration. In this review, we discuss the influence of macrophages on angiogenesis, the process of new blood vessel formation from the pre-existing vasculature. Macrophages play crucial roles at each step of the angiogenic cascade, starting from new blood vessel sprouting to the remodelling of the vascular plexus and vessel maturation. Macrophages form promising targets for both pro- and anti-angiogenic treatments. However, to target macrophages, we will first need to understand the mechanisms that control the functional plasticity of macrophages during each of the steps of the angiogenic cascade. Here, we review recent insights in this topic. Special attention will be given to the TIE2-expressing macrophage (TEM), which is a subtype of highly angiogenic macrophages that is able to influence angiogenesis via the angiopoietin-TIE pathway

Liver grafts procured and discarded by all Belgian centers and transplanted within Eurotransplant network: analysis of cause to decline, a Be-LIAC study

The annual balance between imports and exports of grafts is a matter of debate. We examined the Eurotransplant database of all liver grafts procured within Belgium and Luxemburg which were exported and transplanted abroad. The aim of our study was to analyse the reasons for graft refusal by all Belgian transplant centres and early postoperative evolution. Database between 2015 and 2019 included donor characteristics, reason of offer decline, graft and recipient survival. During the 4 year period 329 grafts were procured in Belgium and transplanted abroad. 163 were exported for HU recipients, 17 no national match recipients (8 AB group, 2 pediatric and 7 other reasons), 19 pay back, 15 splits, 11 not mentioned. Hundred and four grafts were declined by all Belgian centres. Forty seven were declined primary offers and fifty seven livers were distributed by extended allocation. Between them we find out four DCD donors, 83 for medical reasons (age, cytolysis, size mismatch and steatosis). Thirteen livers were accepted and declined at arrival for size mismatch (kept as rescue offer in the same centre). One donor was unstable and two were rejected for positive HCV virology. Only one liver who was primary accepted for a split was transplanted as a whole liver. Two patients presented primary graft nonfunction and three primary graft dysfunction. All of them were retransplanted. Thirteen patients died in the early 3 month postoperative period. Even though higher mortality is expected from marginal grafts, better acceptance rate could be achieved at a national level