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91.
92.
Jacopo Schieppati Bernd Schrittesser Stefano Tagliabue Luca Andena Armin Holzner Jan Poduka Gerald Pinter 《Materials》2022,15(11)
The fatigue behavior of a filled non-crystallizing elastomer was investigated on axisymmetric dumbbell specimens. By plotting relevant Wöhler curves, a power law behavior was found. In addition, temperature increases due to heat build-up were monitored. In order to distinguish between initiation and crack growth regimes, hysteresis curves, secant and dynamic moduli, dissipated and stored energies, and normalized minimum and maximum forces were analyzed. Even though indications related to material damaging were observed, a clear trend to recognize the initiation was not evident. Further details were revealed by considering a fracture mechanics. The analysis of the fracture surfaces evidenced the presence of three regions, associated to initiation, fatigue striation, and catastrophic failure. Additional fatigue tests were performed with samples in which a radial notch was introduced. This resulted in a reduction in lifetime by four orders of magnitude; nevertheless, the fracture surfaces revealed similar failure mechanisms. A fracture mechanics approach, which considered the effect of temperature, was adopted to calculate the critical defect size for fatigue, which was found to be approximately 9 μm. This value was then compared with the particle size distribution obtained through X-ray microcomputed tomography (μ-CT) of undamaged samples and it was found that the majority of the initial defects were indeed smaller than the calculated one. Finally, the evaluation of J-integral for both unnotched and notched dumbbells enabled the assessment of a geometry-independent correlation with fatigue life. 相似文献
93.
Angela Recchia Barbara Rizzi Alessandra Favero Alessandro Nobili Luca Pasina 《Medical principles and practice》2022,31(2):118
ObjectivesThe aim of this study was to assess the prevalence of delirium, using the Assessment Test for Delirium and Cognitive Impairment (4AT) in end-of-life palliative care patients.Subjects and MethodsThis retrospective cross-sectional study was conducted on end-of-life patients in a hospice or at home. All patients were evaluated with the 4AT for the presence of delirium.ResultsOf the 461 patients analyzed, 76 (16.5%) were inpatients and 83.5% (385) outpatients. The median age was 79.5 (72–86) years, and 51.0% were female. According to the 4AT score, 126 patients (27.3%) had delirium (A4T ≥4) at admission, 28 (36.8%) were inpatients, and 98 (25.5%) outpatients. Around 33.8% of the cancer inpatients had delirium, while 20.6% of the cancer outpatients had delirium. The prevalence of delirium varied according to the setting, clinical condition, and life expectancy. In addition, 55.0% (11) actively dying inpatients, within 3 days, had delirium, and 56.7% (17) outpatients had delirium; while among those with life expectancy longer than 4 days, 30.4% (17) inpatients and 22.8% (81) outpatients were with delirium.ConclusionsOur study confirms that delirium is common in cancer and noncancer palliative care patients. Further research on delirium in end-of-life palliative care patients should consider the complexity of palliative care of this population as well as of the characteristics of the settings. 相似文献
94.
Silvia Ferri Bernardo Stefanini Lorenzo Mulazzani Margherita Alvisi Francesco Tovoli Simona Leoni Luca Muratori Tommaso Lotti Alessandro Granito Luigi Bolondi Fabio Piscaglia 《Nutrients》2022,14(12)
The role of moderate alcohol consumption in the evolution of NAFLD is still debated. The aim of this study is to evaluate the impact of current and lifelong alcohol consumption in patients with NAFLD. From 2015 to 2020, we enrolled 276 consecutive patients fulfilling criteria of NAFLD (alcohol consumption up to 140 g/week for women and 210 g/week for men). According to their current alcohol intake per week, patients were divided in: abstainers, very low consumers (C1: <70 g/week) and moderate consumers (C2). We created a new tool, called LACU (Lifetime Alcohol Consuming Unit) to estimate the alcohol exposure across lifetime: 1 LACU was defined as 7 alcohol units per week for 1 drinking year. Patients were divided into lifelong abstainers and consumers and the latter furtherly divided into quartiles: Q1-Q4. Stratification according to alcohol intake, both current and cumulative as estimated by LACU, showed that very low consumers (C1 and Q1-Q3) displayed lower frequency of cirrhosis and hepatocellular carcinoma compared to abstainers and moderate consumers (C2 and Q4). We can speculate that up to one glass of wine daily in the context of a Mediterranean diet may be a long-term useful approach in selected NAFLD patients. 相似文献
95.
Federico Belladelli Luca Boeri Paolo Capogrosso Walter Cazzaniga Eugenio Ventimiglia Luigi Candela Edoardo Pozzi Andrea Baudo Massimo Alfano Costantino Abbate Francesco Montorsi Andrea Salonia 《Asian journal of andrology》2021,(5):456-461
Substances of abuse(SoA),as well as smoking and alcohol consumption,are well known for their impact on male fertility status,erectile function,and ejaculation.W... 相似文献
96.
Eleonora Loi Cesare Zavattari Alessandro Tommasi Loredana Moi Matteo Canale Agnese Po Claudia Sabato Ana Florencia Vega-Benedetti Pina Ziranu Marco Puzzoni Eleonora Lai Luca Faloppi María Rulln Juan Carrascosa Irene Amat Jesús M. Urman Maria Arechederra Carmen Berasain Elisabetta Ferretti Andrea Casadei-Gardini Matías A. Avila Sergio Alonso Mario Scartozzi Patrizia Zavattari 《British journal of cancer》2022,126(12):1783
Background Biliary tract cancers (BTC) are rare but highly aggressive tumours with poor prognosis, usually detected at advanced stages. Herein, we aimed at identifying BTC-specific DNA methylation alterations.Methods Study design included statistical power and sample size estimation. A genome-wide methylation study of an explorative cohort (50 BTC and ten matched non-tumoral tissue samples) has been performed. BTC-specific altered CpG islands were validated in over 180 samples (174 BTCs and 13 non-tumoral controls). The final biomarkers, selected by a machine-learning approach, were validated in independent tissue (18 BTCs, 14 matched non-tumoral samples) and bile (24 BTCs, five non-tumoral samples) replication series, using droplet digital PCR.Results We identified and successfully validated BTC-specific DNA methylation alterations in over 200 BTC samples. The two-biomarker panel, selected by an in-house algorithm, showed an AUC > 0.97. The best-performing biomarker (chr2:176993479-176995557), associated with HOXD8, a pivotal gene in cancer-related pathways, achieved 100% sensitivity and specificity in a new series of tissue and bile samples.Conclusions We identified a novel fully efficient BTC biomarker, associated with HOXD8 gene, detectable both in tissue and bile by a standardised assay ready-to-use in clinical trials also including samples from non-invasive matrices.Subject terms: Diagnostic markers, Biliary tract cancer 相似文献
97.
98.
99.
Luca Voltolini Alberto Salvicchi Giovanni Cianchi Stefano Bongiolatti 《Interactive Cardiovascular and Thoracic Surgery》2022,35(1)
Carinal re-resection for tumour recurrence is rarely performed due to increased difficulty in airway reconstruction. We reported a successful case of carinal resection and reconstruction for recurrent chondrosarcoma after previous distal tracheal resection. Due to the technical complexity of the reconstruction and the poor respiratory reserve of the patient, the veno-venous extracorporeal membrane oxygenation support was used. 相似文献