Ottimizzazione di celle a combustibile ad elettrolita polimerico ad elevate prestazioni: un approccio termoenergetico

Il presente lavoro, partendo dall’analisi delle caratteristiche che hanno portato a preferire le celle a combustibile ad elettrolita polimerico rispetto alle altre tipologie di celle presenti in letteratura tecnica, si occupa del management termico di questi sistemi di conversione diretta dell’energia chimica in energia elettrica interfacciando tale studio ai vari ambiti disciplinari propri delle celle a combustibile. Lo scopo della tesi è quello di ottimizzare i sistemi convenzionali di controllo termico delle celle a combustibile ad elettrolita polimerico, che asportano il calore in eccesso per circolazione forzata di aria all’interno di canali ricavati nelle piastre bipolari, e di valutare le prospettive dei sistemi non convenzionali di management termico (ad esempio sistemi bifase) che meglio si adattano alle celle a combustibile ad elevate prestazioni. Sono state infine illustrate le linee guida per ottimizzare il sistema di controllo termico delle celle a combustibile ad elettrolita polimerico. Tramite un approccio di tipo termoenergetico, capace di accoppiare il problema termico a quello fluidodinamico, è stata delineata una procedura di ottimizzazione multi obiettivo in grado di studiare problematiche di tipo termico - fluidodinamico unitamente a vincoli di tipo elettrico e chimico. Come caso studio poi, è stato utilizzato lo stack di celle a combustibile FC-019K-5 della H2ECOnomy di proprietà del Dipartimento di Energetica “L. Poggi” dell’Università di Pisa, verificando come il sistema di controllo termico per questa cella a combustibile commerciale non sia di fatto ottimizzato, proponendo quindi soluzioni alternative

Free-style technique versus computed tomographic angiography-guided perforator selection in deep inferior epigastric perforator flap harvest: a prospective clinical study

Background: Computed tomographic angiography (CTA) is the preferred diagnostic tool in preoperative deep inferior epigastric perforator (DIEP) flap assessment, though some surgeons prefer approaching perforator selection with intraoperative findings alone. Methods: This prospective observational study conducted between 2015 and 2020 assessed our intraoperative decision-making "free-style" technique for DIEP flap harvest. Any patient with indication for immediate or delayed breast reconstruction using abdominally based flaps and who received preoperative CTA was enrolled. Only unilateral cases performed by the same surgeon were considered. Allergy to iodine-based contrast media, renal impairment and claustrophobia were other exclusion criteria. Primary endpoint consisted in comparing operative times and complication rates between free-style technique and CTA-guided approach. Secondary endpoints included evaluation of agreement rate between intraoperative findings and CTA, and identification of variables affecting operative time and complication rate. Demographics, surgical information, agreement versus non-agreement and complications were collected. Results: Starting from 206 patients, 100 were enrolled. Fifty were assigned to Group A, receiving DIEP flap with free-style technique. The other 50 were assigned to Group B, receiving DIEP flap with CTA-guided perforators selection. Study groups' demographics were homogenous. Operative time was statistically lower (p = .036) in free-style group (252.4 ± 44.77 min vs. 265.6 ± 31.67 min). Complication rates were higher in CTA-guided group (10% vs. 2%) though this was not significant (p = .092). Overall agreement rate in dominant perforator selection between intraoperatively and CTA-based assessment was 81%. Multiple regression analysis showed no variable increased complication rate, though CTA-guided approach, BMI > 30 and harvesting more than one perforator were respectively associated with B-coefficient of 17.391 (2.430-32.351, 95% CI) [p = .023], 3.50 (0.640-6.379, 95% CI) [p = .017] and 18.887 (6.232-31.542, 95% CI) [p = .004], predicting increased operative time. Conclusions: The free-style technique proved to be a useful tool for guiding DIEP flap harvest with good sensibility in detecting the dominant perforator suggested by CTA without statistically increasing surgery duration and complications

Determining Breast Implant Prevalence. A Population Study of Italian Chest Radiographs

Background Current breast implant prevalence within the general population remains elusive. An accurate prevalence is critical to serve as the denominator for any assessment of breast implant-related complication. The purpose of this manuscript is to assess this prevalence in women aged 20-70 years in Italy.Materials and Methods Eight reviewers, demonstrating a mean sensitivity of 87.0% and specificity of 97.0%, were recruited for retrospective identification of implants on chest radiographs from a tertiary academic hospital in a major urban setting. Three final reviewers were selected, and they assessed all eligible chest radiographs collected between January and December 2019. The hospital-based population was compared to epidemiological data at a local, regional and national level to demonstrate homogeneity of age structures using the phi correlation coefficient.Results We identified 3,448 chest X-rays which yielded 140 implants, with an overall prevalence of 4.1% for women aged 20-70. Implants were bilateral in 76% of cases and unilateral in 24%. They were placed cosmetically in 47.1% cases and used for reconstruction in 52.9% cases. Phi correlation coefficient found no differences across hospital-based, local, regional and national populations.Conclusion A validated method was performed to estimate implant prevalence from an academic hospital in a major urban setting at 4.1% and was used to estimate national prevalence in Italy. The implications of this epidemiologic study may reach across national borders for improved understanding of breast implant epidemiology and in predicting the total number of patients within a given population that may be affected by device complications

New-Onset Refractory Status Epilepticus with Claustrum Damage: Definition of the Clinical and Neuroimaging Features

New-onset refractory status epilepticus (NORSE) is a rare but challenging condition occurring in a previously healthy patient, often with no identifiable cause. We describe the electro-clinical features and outcomes in a group of patients with NORSE who all demonstrated a typical magnetic resonance imaging (MRI) sign characterized by bilateral lesions of the claustrum. The group includes 31 patients (12 personal and 19 previously published cases; 17 females; mean age of 25 years). Fever preceded status epilepticus (SE) in 28 patients, by a mean of 6 days. SE was refractory/super-refractory in 74% of the patients, requiring third-line agents and a median of 15 days staying in an intensive care unit. Focal motor and tonic-clonic seizures were observed in 90%, complex partial seizures in 14%, and myoclonic seizures in 14% of the cases. All patients showed T2/FLAIR hyperintense foci in bilateral claustrum, appearing on average 10 days after SE onset. Other limbic (hippocampus, insular) alterations were present in 53% of patients. Within the personal cases, extensive search for known autoantibodies was inconclusive, though 7 of 11 patients had cerebrospinal fluid lymphocytic pleocytosis and 3 cases had oligoclonal bands. Two subjects died during the acute phase, one in the chronic phase (probable sudden unexplained death in epilepsy), and one developed a persistent vegetative state. Among survivors, 80% developed drug-resistant epilepsy. Febrile illness-related SE associated with bilateral claustrum hyperintensity on MRI represents a condition with defined clinical features and a presumed but unidentified autoimmune etiology. A better characterization of de novo SE is mandatory for the search of specific etiologies

Clinical recommendations for diagnosis and treatment according to current updated knowledge on BIA-ALCL

Shared strategies and correct information are essential to guide physicians in the management of such an uncommon disease as Breast Implant-Associated Anaplastic Large Cell Lymphoma (BIA-ALCL). A systematic review of the literature was performed to collect the most relevant evidence on BIA-ALCL reported cases. A panel of multidisciplinary experts discussed the scientific evidence on BIA-ALCL, and updated consensus recommendations were developed through the Delphi process. The lastest reported Italian incidence of BIA-ALCL is 3.5 per 100.000 implanted patients (95% CI, 1.36 to 5.78), and the disease counts over 1216 cases worldwide as of June 2022. The most common presentation symptom is a late onset seroma followed by a palpable breast mass. In the event of a suspicious case, ultrasound-guided fine-needle aspiration should be the first step in evaluation, followed by cytologic and immunohistochemical examination. In patients with confirmed diagnosis of BIA-ALCL confined to the capsule, the en-bloc capsulectomy should be performed, followed by immediate autologous reconstruction, while delayed reconstruction applies for disseminate disease or radically unresectable tumor. Nevertheless, a multidisciplinary team approach is essential for the correct management of this pathology

Association of CSF and PET markers of neurodegeneration with electroclinical progression in Lafora disease

PurposeTo evaluate the electro-clinical features in association with laboratory and instrumental correlates of neurodegeneration to detect the progression of Lafora disease (LD).MethodsWe investigated the electro-clinical longitudinal data and CSF Aβ42, p-tau181 and t-tauAg, amyloid, and 18F-FDG PET of five unrelated LD families.ResultsThree progressive electro-clinical stages were identified. The early phase was characterized by rare, generalized tonic-clonic and focal visual seizures, followed by the occurrence of myoclonus after a period ranging from 2 to 12 months. The intermediate stage, usually occurring 2 years after the onset of epilepsy, is characterized by a worsening of epilepsy and myoclonus associated with progressive dementia and cerebellar signs. Finally, the late stage, evolving after a mean period of 7 ± 1.41 years from the onset of the disease, was characterized by gait ataxia resulting in bedriddenness, severe dementia, daily/pluri-daily myoclonus, drug-resistant epilepsy, clusters of seizures or status epilepticus, and medical complications. Amyloid (CSF Aβ42, amyloid PET) and neurodegenerative (CSF p-tau181 and t-tauAg, FDG-PET) biomarkers indicate a pattern of cognitive impairment of the non-Alzheimer's disease type. A total of 80% of the LD patients showed more severe hypometabolism in the second FDG-PET scan compared to the first scan performed in a lower phase; the lateral temporal lobe and the thalamus hypometabolism were associated with the presence of intermediate or late phase.ConclusionsThree electroclinical and 18F-FDG PET evolutive stages are useful biomarkers for the progression of LD and could help to evaluate the efficacy of new disease-modifying treatments. The combination of traditional CSF biomarkers improves the diagnostic accuracy of cognitive decline in LD patients, indicating a cognitive impairment of the non-Alzheimer's disease type

Contribution of ultrarare variants in mTOR pathway genes to sporadic focal epilepsies

Objective: We investigated the contribution to sporadic focal epilepsies (FE) of ultrarare variants in genes coding for the components of complexes regulating mechanistic Target Of Rapamycin (mTOR)complex 1 (mTORC1). Methods: We collected genetic data of 121 Italian isolated FE cases and 512 controls by Whole Exome Sequencing (WES) and single-molecule Molecular Inversion Probes (smMIPs) targeting 10 genes of the GATOR1, GATOR2, and TSC complexes. We collapsed “qualifying” variants (ultrarare and predicted to be deleterious or loss of function) across the examined genes and sought to identify their enrichment in cases compared to controls. Results: We found eight qualifying variants in cases and nine in controls, demonstrating enrichment in FE patients (P = 0.006; exact unconditional test, one-tailed). Pathogenic variants were identified in DEPDC5 and TSC2, both major genes for Mendelian FE syndromes. Interpretation: Our findings support the contribution of ultrarare variants in genes in the mTOR pathway complexes GATOR and TSC to the risk of sporadic FE and a shared genetic basis between rare and common epilepsies. The identification of a monogenic etiology in isolated cases, most typically encountered in clinical practice, may offer to a broader community of patients the perspective of precision therapies directed by the underlying genetic cause

Rising rural body-mass index is the main driver of the global obesity epidemic in adults

Body-mass index (BMI) has increased steadily in most countries in parallel with a rise in the proportion of the population who live in cities(.)(1,2) This has led to a widely reported view that urbanization is one of the most important drivers of the global rise in obesity(3-6). Here we use 2,009 population-based studies, with measurements of height and weight in more than 112 million adults, to report national, regional and global trends in mean BMI segregated by place of residence (a rural or urban area) from 1985 to 2017. We show that, contrary to the dominant paradigm, more than 55% of the global rise in mean BMI from 1985 to 2017-and more than 80% in some low- and middle-income regions-was due to increases in BMI in rural areas. This large contribution stems from the fact that, with the exception of women in sub-Saharan Africa, BMI is increasing at the same rate or faster in rural areas than in cities in low- and middle-income regions. These trends have in turn resulted in a closing-and in some countries reversal-of the gap in BMI between urban and rural areas in low- and middle-income countries, especially for women. In high-income and industrialized countries, we noted a persistently higher rural BMI, especially for women. There is an urgent need for an integrated approach to rural nutrition that enhances financial and physical access to healthy foods, to avoid replacing the rural undernutrition disadvantage in poor countries with a more general malnutrition disadvantage that entails excessive consumption of low-quality calories.Peer reviewe

Worldwide trends in hypertension prevalence and progress in treatment and control from 1990 to 2019: a pooled analysis of 1201 population-representative studies with 104 million participants

Background Hypertension can be detected at the primary health-care level and low-cost treatments can effectively control hypertension. We aimed to measure the prevalence of hypertension and progress in its detection, treatment, and control from 1990 to 2019 for 200 countries and territories. Methods We used data from 1990 to 2019 on people aged 30–79 years from population-representative studies with measurement of blood pressure and data on blood pressure treatment. We defined hypertension as having systolic blood pressure 140 mm Hg or greater, diastolic blood pressure 90 mm Hg or greater, or taking medication for hypertension. We applied a Bayesian hierarchical model to estimate the prevalence of hypertension and the proportion of people with hypertension who had a previous diagnosis (detection), who were taking medication for hypertension (treatment), and whose hypertension was controlled to below 140/90 mm Hg (control). The model allowed for trends over time to be non-linear and to vary by age. Findings The number of people aged 30–79 years with hypertension doubled from 1990 to 2019, from 331 (95% credible interval 306–359) million women and 317 (292–344) million men in 1990 to 626 (584–668) million women and 652 (604–698) million men in 2019, despite stable global age-standardised prevalence. In 2019, age-standardised hypertension prevalence was lowest in Canada and Peru for both men and women; in Taiwan, South Korea, Japan, and some countries in western Europe including Switzerland, Spain, and the UK for women; and in several low-income and middle-income countries such as Eritrea, Bangladesh, Ethiopia, and Solomon Islands for men. Hypertension prevalence surpassed 50% for women in two countries and men in nine countries, in central and eastern Europe, central Asia, Oceania, and Latin America. Globally, 59% (55–62) of women and 49% (46–52) of men with hypertension reported a previous diagnosis of hypertension in 2019, and 47% (43–51) of women and 38% (35–41) of men were treated. Control rates among people with hypertension in 2019 were 23% (20–27) for women and 18% (16–21) for men. In 2019, treatment and control rates were highest in South Korea, Canada, and Iceland (treatment >70%; control >50%), followed by the USA, Costa Rica, Germany, Portugal, and Taiwan. Treatment rates were less than 25% for women and less than 20% for men in Nepal, Indonesia, and some countries in sub-Saharan Africa and Oceania. Control rates were below 10% for women and men in these countries and for men in some countries in north Africa, central and south Asia, and eastern Europe. Treatment and control rates have improved in most countries since 1990, but we found little change in most countries in sub-Saharan Africa and Oceania. Improvements were largest in high-income countries, central Europe, and some upper-middle-income and recently high-income countries including Costa Rica, Taiwan, Kazakhstan, South Africa, Brazil, Chile, Turkey, and Iran. Interpretation Improvements in the detection, treatment, and control of hypertension have varied substantially across countries, with some middle-income countries now outperforming most high-income nations. The dual approach of reducing hypertension prevalence through primary prevention and enhancing its treatment and control is achievable not only in high-income countries but also in low-income and middle-income settings

Worldwide trends in hypertension prevalence and progress in treatment and control from 1990 to 2019: a pooled analysis of 1201 population-representative studies with 104 million participants.

BACKGROUND: Hypertension can be detected at the primary health-care level and low-cost treatments can effectively control hypertension. We aimed to measure the prevalence of hypertension and progress in its detection, treatment, and control from 1990 to 2019 for 200 countries and territories. METHODS: We used data from 1990 to 2019 on people aged 30-79 years from population-representative studies with measurement of blood pressure and data on blood pressure treatment. We defined hypertension as having systolic blood pressure 140 mm Hg or greater, diastolic blood pressure 90 mm Hg or greater, or taking medication for hypertension. We applied a Bayesian hierarchical model to estimate the prevalence of hypertension and the proportion of people with hypertension who had a previous diagnosis (detection), who were taking medication for hypertension (treatment), and whose hypertension was controlled to below 140/90 mm Hg (control). The model allowed for trends over time to be non-linear and to vary by age. FINDINGS: The number of people aged 30-79 years with hypertension doubled from 1990 to 2019, from 331 (95% credible interval 306-359) million women and 317 (292-344) million men in 1990 to 626 (584-668) million women and 652 (604-698) million men in 2019, despite stable global age-standardised prevalence. In 2019, age-standardised hypertension prevalence was lowest in Canada and Peru for both men and women; in Taiwan, South Korea, Japan, and some countries in western Europe including Switzerland, Spain, and the UK for women; and in several low-income and middle-income countries such as Eritrea, Bangladesh, Ethiopia, and Solomon Islands for men. Hypertension prevalence surpassed 50% for women in two countries and men in nine countries, in central and eastern Europe, central Asia, Oceania, and Latin America. Globally, 59% (55-62) of women and 49% (46-52) of men with hypertension reported a previous diagnosis of hypertension in 2019, and 47% (43-51) of women and 38% (35-41) of men were treated. Control rates among people with hypertension in 2019 were 23% (20-27) for women and 18% (16-21) for men. In 2019, treatment and control rates were highest in South Korea, Canada, and Iceland (treatment >70%; control >50%), followed by the USA, Costa Rica, Germany, Portugal, and Taiwan. Treatment rates were less than 25% for women and less than 20% for men in Nepal, Indonesia, and some countries in sub-Saharan Africa and Oceania. Control rates were below 10% for women and men in these countries and for men in some countries in north Africa, central and south Asia, and eastern Europe. Treatment and control rates have improved in most countries since 1990, but we found little change in most countries in sub-Saharan Africa and Oceania. Improvements were largest in high-income countries, central Europe, and some upper-middle-income and recently high-income countries including Costa Rica, Taiwan, Kazakhstan, South Africa, Brazil, Chile, Turkey, and Iran. INTERPRETATION: Improvements in the detection, treatment, and control of hypertension have varied substantially across countries, with some middle-income countries now outperforming most high-income nations. The dual approach of reducing hypertension prevalence through primary prevention and enhancing its treatment and control is achievable not only in high-income countries but also in low-income and middle-income settings. FUNDING: WHO