Dynamics of a vapor nanobubble collapsing near a solid boundary

In the present paper a diffuse interface approach is used to address the collapse of a sub-micron vapor bubble near solid boundaries. This formulation enables an unprecedented description of interfacial flows that naturally takes into account topology modification and phase changes (both vapor/liquid and vapor/supercritical fluid transformations). Results from numerical simulations are exploited to discuss the complex sequence of events associated with the bubble collapse near a wall, encompassing shock-wave emissions in the liquid and reflections from the wall, their successive interaction with the expanding bubble, the ensuing asymmetry of the bubble and the eventual jetting phase

Dynamic Adaptation of the Distributed Election Procedure in IEEE 802.16 WMNs

The goal is to propose an algorithm wich gives to every node of the mesh network the possibility to adapt the holdoff time dynamically and than evaluate the performance

On the benefits of domain adaptation techniques for quality of transmission estimation in optical networks

Machine learning (ML) is increasingly applied in optical network management, especially in cross-layer frameworks where physical layer characteristics may trigger changes at the network layer due to transmission performance measurements (quality of transmission, QoT) monitored by optical equipment. Leveraging ML-based QoT estimation approaches has proven to be a promising alternative to exploiting classical mathematical methods or transmission simulation tools. However, supervised ML models rely on large representative training sets, which are often unavailable, due to the lack of the necessary telemetry equipment or of historical data. In such cases, it can be useful to use training data collected from a different network. Unfortunately, the resulting models may be uneffective when applied to the current network, if the training data (the source domain) is not well representative of the network under study (the target domain). Domain adaptation (DA) techniques aim at tackling this issue, to make possible the transfer of knowledge among different networks. This paper compares several DA approaches applied to the problem of estimating the QoT of an optical lightpath using a supervised ML approach. Results show that, when the number of samples from the target domain is limited to a few dozen, DA approaches consistently outperform standard supervised ML techniques

Shock-induced collapse of a vapor nanobubble near solid boundaries

The collapse of a nano-bubble near a solid wall is addressed here exploiting a phase field model recently used to describe the process in free space. Bubble collapse is triggered by a normal shock wave in the liquid. The dynamics is explored for different bubble wall normal distances and triggering shock inten- sities. Overall the dynamics is characterized by a sequence of collapses and rebounds of the pure vapor bubble accompanied by the emission of shock waves in the liquid. The shocks are reflected by the wall to impinge back on the re-expanding bubble. The presence of the wall and the impinging shock wave break the symmetry of the system, leading, for su ffi ciently strong intensity of the incoming shock wave, to the poration of the bubble and the formation of an annular structure and a liquid jet. Intense peaks of pres- sure and temperatures are found also at the wall, confirming that the strong localized loading combined with the jet impinging the wall is a potential source of substrate damage induced by the cavitation

Montagne, comunità e lavoro tra 14. e 18. secolo

Il tema del volume è la definizione del rapporto tra comunità e lavoro in ambito alpino e prealpino. L’ambiente delle Alpi, infatti, ha determinato forme specifiche di organizzazione del lavoro e della proprietà, per esempio enfatizzando il ruolo della gestione collettiva dei beni fondiari, ma, al tempo stesso, l’organizzazione del lavoro ha modificato e connotato diversamente la vita delle comunità montane rispetto a quella delle comunità di pianura. Le aree alpine fornivano opportunità non sempre presenti altrove: attività di sfruttamento dei boschi e delle acque, di guida e di someggiatura legate ai passi e ai transiti di viaggiatori, erano solo alcuni degli ambiti di lavoro possibili in queste zone. I testi che il lettore troverà nel volume sono stati organizzati in cinque sezioni: la prima dedicata alle necessità collettive e alle risorse locali, la seconda all’organizzazione del lavoro, la terza agli scambi e al commercio, la quarta alle infrastrutture e, infine, in funzione comparativa e di confronto, una quinta sezione rivolta ad “altre montagne”

Orofacial Migraine and Other Idiopathic Non-Dental Facial Pain Syndromes: A Clinical Survey of a Social Orofacial Patient Group

: Background: Orofacial pain syndromes (OFPs) are a heterogeneous group of syndromes mainly characterized by painful attacks localized in facial and oral structures. According to the International Classification of Orofacial Pain (ICOP), the last three groups (non-dental facial pain, NDFP) are cranial neuralgias, facial pain syndromes resembling primary headache syndromes, and idiopathic orofacial pain. These are often clinical challenges because the symptoms may be similar or common among different disorders. The diagnostic efforts often induce a complex diagnostic algorithm and lead to several imaging studies or specialized tests, which are not always necessary. The aim of this study was to describe the encountered difficulties by these patients during the diagnostic-therapeutic course. Methods: This study was based on the responses to a survey questionnaire, administered to an Italian Facebook Orofacial Patient Group, searching for pain characteristics and diagnostic-therapeutic care courses. The questionnaire was filled out by patients affected by orofacial pain, who were 18 years and older, using a free online tool available on tablets, smartphones, and computers. Results: The sample was composed of 320 subjects (244F/76M), subdivided by age range (18-35 ys: 17.2%; 36-55 ys: 55.0%; >55 ys 27.8%). Most of the patients were affected by OFP for more than 3 years The sample presented one OFP diagnosis in 60% of cases, more than one in 36.2% of cases, and 3.8% not classified. Trigeminal neuralgia is more represented, followed by cluster headaches and migraines. About 70% had no pain remission, showing persisting background pain (VAS median = 7); autonomic cranial signs during a pain attack ranged between 45 and 65%. About 70% of the subjects consulted at least two different specialists. Almost all received drug treatment, about 25% received four to nine drug treatments, 40% remained unsatisfied, and almost 50% received no pharmacological treatment, together with drug therapy. Conclusion: To the authors' knowledge, this is the first study on an OFP population not selected by a third-level specialized center. The authors believe this represents a realistic perspective of what orofacial pain subjects suffer during their diagnostic-therapeutic course and the medical approach often results in unsatisfactory outcomes

Aldo-Keto Reductase 1C1 (AKR1C1) as the first mutated gene in a family with nonsyndromic primary lipedema

Lipedema is an often underdiagnosed chronic disorder that affects subcutaneous adipose tissue almost exclusively in women, which leads to disproportionate fat accumulation in the lower and upper body extremities. Common comorbidities include anxiety, depression, and pain. The correlation between mood disorder and subcutaneous fat deposition suggests the involvement of steroids metabolism and neurohormones signaling, however no clear association has been established so far. In this study, we report on a family with three patients affected by sex-limited autosomal dominant nonsyndromic lipedema. They had been screened by whole exome sequencing (WES) which led to the discovery of a missense variant p.(Leu213Gln) in AKR1C1, the gene encoding for an aldo-keto reductase catalyzing the reduction of progesterone to its inactive form, 20-\u3b1-hydroxyprogesterone. Comparative molecular dynamics simulations of the wild-type vs. variant enzyme, corroborated by a thorough structural and functional bioinformatic analysis, suggest a partial loss-of-function of the variant. This would result in a slower and less efficient reduction of progesterone to hydroxyprogesterone and an increased subcutaneous fat deposition in variant carriers. Overall, our results suggest that AKR1C1 is the first candidate gene associated with nonsyndromic lipedema

Association between Food Intake, Clinical and Metabolic Markers and DNA Damage in Older Subjects

Abstract The use of DNA damage as marker of oxidative stress, metabolic dysfunction and age-related diseases is debated. The present study aimed at assessing the level of DNA damage (evaluated as DNA strand-breaks, endogenous and oxidatively-induced DNA damage) in a group of older subjects with intestinal permeability enrolled within the MaPLE (Gut and Blood Microbiomics for Studying the Effect of a Polyphenol-Rich Dietary Pattern on Intestinal Permeability in the Elderly) intervention trial, to evaluate its association with clinical, metabolic and dietary markers. DNA damage in peripheral blood mononuclear cells was assessed by the comet assay in 49 older subjects participating in the study. Clinical and metabolic markers, markers of inflammation, vascular function and intestinal permeability were determined in serum. Food intake was estimated by weighted food diaries. On the whole, a trend towards higher levels of DNA damage was observed in men compared to women (p = 0.071). A positive association between DNA damage and clinical/metabolic markers (e.g., uric acid, lipid profile) and an inverse association with dietary markers (e.g., vitamin C, E, B6, folates) were found and differed based on sex. By considering the importance of DNA stability during aging, the results obtained on sex differences and the potential role of dietary and metabolic factors on DNA damage underline the need for further investigations in a larger group of older adults to confirm the associations found and to promote preventive strategies

Systematic Review on Polyphenol Intake and Health Outcomes: Is there Sufficient Evidence to Define a Health-Promoting Polyphenol-Rich Dietary Pattern?

Growing evidence support association between polyphenol intake and reduced risk for chronic diseases, even if there is a broad debate about the effective amount of polyphenols able to exert such protective effect. The present systematic review provides an overview of the last 10-year literature on the evaluation of polyphenol intake and its association with specific disease markers and/or endpoints. An estimation of the mean total polyphenol intake has been performed despite the large heterogeneity of data reviewed. In addition, the contribution of dietary sources was considered, suggesting tea, coffee, red wine, fruit and vegetables as the main products providing polyphenols. Total flavonoids and specific subclasses, but not total polyphenols, have been apparently associated with a low risk of diabetes, cardiovascular events and all-cause mortality. However, large variability in terms of methods for the evaluation and quantification of polyphenol intake, markers and endpoints considered, makes it still difficult to establish an evidence-based reference intake for the whole class and subclass of compounds. Nevertheless, the critical mass of data available seem to strongly suggest the protective effect of a polyphenol-rich dietary pattern even if further well targeted and methodologically sound research should be encouraged in order to define specific recommendation