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Introduction: Tricuspid regurgitation (TR) is a relatively common valvular disease, which can result from structural abnormalities of any anatomic part of the tricuspid valve. Severe TR is linked to congestive heart failure and hemodynamic impairment, resulting in high mortality when repaired by elective surgery. This study was undertaken to quantify the structural and hemodynamic performance of the novel Transcatheter Bicaval Valves System (TricValve) percutaneously implanted in the superior vena cava (SVC) and inferior vena cava (IVC) of two patients with severe TR and venous congestion.Methods: After developing the SVC and IVC device models, the contact pressure exerted on the vena cava wall was obtained by computational analysis. Both smoothed-particle hydrodynamics (SPH) and computational fluid dynamics were carried out to quantify caval reflux in the right atrium and the pressure field of pre- and post-TricValve scenarios, respectively.Results: Analysis of contact pressure highlighted the main anchoring area of the SVC device occurring near the SVC device belly, while the IVC device exerted pronounced forces in the device’s proximal and distal parts. SPH-related flow velocities revealed the absence of caval reflux, and a decrease in time-averaged pressure was observed near the SVC and IVC after TricValve implantation.Discussion: Findings demonstrated the potential of computational tools for enhancing our understanding of the biomechanical performance of structural tricuspid valve interventions and improving the way we design next-generation transcatheter therapies to treat the tricuspid valve with heterotopic caval valve implantation.

Background: University counselling services assume a fundamental support function for students who are facing moments of crisis during their academic career. Such services often aim to reduce drop-out rates and achieve improvement in terms of psychological well-being. COVID-19 contagion containment measures have also had an impact on the psychological health of university students and their ability to cope with important developmental tasks. It has become necessary, therefore, to offer online counselling services which has become, however, the means of choice to support students during the university course in the pandemic era, as a complementary intervention to the traditional face-to-face approach. Methods: In a clinical and health psychology perspective, this study aims to analyze the efficacy of 13 online counselling groups involving 66 underachieving students, lagging with their studies. The intervention has adopted the methodology of the Narrative Mediation Path, which aims at promoting mentalization, academic engagement and psychological well-being in order to have an impact on students’ academic performance and prevent university dropouts. At the beginning and end of counselling the following measures were administered: a) Reflective Functioning Questionnaire, b) Psychological General Well-Being Index Short Form, c) Academic Performance Inventory, d) University Student Engagement Inventory, e) Group Climate Questionnaire. Results: The results showed that online counselling groups enabled an overall improvement in all the variables considered. Conclusion: Overall, the present study showed the efficacy of the online group counselling service in supporting students during the pandemic period and in coping with the difficulties encountered during the academic career.

This article is a case study of how educators made sense of the core ideas of a new statewide initiative intentionally designed to foster local flexibility. We trace the initiative's core elements through (1) communication materials, (2) school principals' understandings of the initiative and reasons for participation, and (3) teachers' understandings of what the initiative required of them. Using interviews from principals and teachers, this article sheds light on tensions between providing flexibility and ensuring integrity to core components. Overall, our findings suggest that while principals understood the core elements of the initiative, some elements were pushed to the front and others were pushed to the back.

Abstract Aims We hypothesized that left atrial (LA) remodelling and function are associated with poor exercise capacity as prognostic marker in chronic heart failure (CHF) across a broad range of left ventricular ejection fraction (LVEF). Methods and results One hundred seventy‐one patients with CHF were analysed [age 65 ± 11 years, 136 males (80%); 86 heart failure with reduced ejection fraction (HFrEF), 27 heart failure with mid‐range ejection fraction (HFmrEF), 58 heart failure with preserved ejection fraction (HFpEF)]. All patients underwent echocardiography and maximal cardiopulmonary exercise testing and were classified according to a prognostic cut‐off of peak VO2 (pVO2; 14 mL/kg/min). Seventy‐seven (45%) patients reached pVO2

The growing awareness of tricuspid regurgitation (TR) and the fast-expanding array of devices aiming to percutaneously repair or replace the tricuspid valve have underscored the central role of multi-modality imaging in comprehensively assessing the anatomical and functional characteristics of TR. Accurate phenotyping of TR, the right heart, and pulmonary vasculature via echocardiography, computed tomography, and, occasionally, cardiovascular magnetic resonance and right heart catheterization is deemed crucial in choosing the most suitable treatment strategy for each patient and achieving procedural success. In the first part of the present review, key imaging factors for patient selection will be discussed. In the ensuing sections, an overview of the most commonly used, commercially available systems for transcatheter repair/replacement will be presented, along with their respective selection criteria and information on intraprocedural imaging guidance; these are edge-to-edge repair, orthotopic and heterotopic replacement, and valve-in-valve procedures. [ABSTRACT FROM AUTHOR]

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Background Acute mitral regurgitation due to papillary muscle rupture is a severe complication of acute myocardial infarction. Transcatheter edge-to-edge repair is emerging as an effective alternative to surgical treatment, with encouraging outcomes. Leaflet adverse events are rare and are associated with relapse of significant mitral regurgitation. Case summary A 54-year-old man arrived at our hospital with a late presentation of ST-elevation myocardial infarction. During primary percutaneous coronary intervention of the circumflex coronary artery, a partial papillary muscle rupture occurred with acute severe mitral regurgitation and cardiogenic shock. Due to the severe haemodynamic instability, the patient underwent an emergent transcatheter edge-to-edge repair with MitraClip device during Impella support with mitral regurgitation resolution and haemodynamic stabilization. At 2-month follow-up, an interclip leaflet tear occurred with relapse of severe mitral regurgitation, requiring a mitral valve replacement surgery. Discussion Acute mitral regurgitation due to papillary muscle rupture is a serious complication of acute myocardial infarction. Management is based on haemodynamic stabilization and surgery. The transcatheter edge-to-edge repair is emerging as a therapeutic alternative in high-risk cases. Leaflet adverse events rarely occur during the transcatheter edge-to-edge repair procedure or before patient discharge. Our case is the first to report a late leaflet adverse event, occurring two months after the procedure and, interestingly, after an acute myocardial infarction conditioning an ischaemic mitral regurgitation. This event may be the result of the progressive adverse remodelling of left ventricular inferolateral akinetic wall, with consequent increase of tethering forces on the posterior leaflet, tensioned in the opposite direction by the clip. [ABSTRACT FROM AUTHOR]

Bone fragility is a recognized complication of type 2 diabetes mellitus (T2DM), increasing patient morbidity. Thus, the development of an effective intervention to prevent diabetic bone fragility is urgently needed. As lifestyle intervention represents an effective option for diabetes management, it may have an impact on bone health. While studies have shown a beneficial effect of dietary fiber in T2DM management, its effect on bone health is still unclear. Thus, we investigated the impact of a high-fiber diet on bone and glucose control in men and women with T2DM. Forty-five T2DM patients (HbA1c: 6.5% ± 0.49%, age: 74 ± 7.29 yr) scheduled for hip arthroplasty were randomly assigned to follow a high-fiber diet (38 g/day) or to make no diet changes for 12 wk. Interestingly, BMI decreased by 4% (p <.0001) and HbA1c by 3.4% (p <.0001) in the high-fiber diet group, but did not decrease in the control group. However, serum concentration of the bone formation marker procollagen type 1 amino-terminal propeptide (P1NP) decreased by 8.6 % in the high-fiber diet group (p =.0004), whereas it remained unchanged in the control group. In contrast, similar to the control group, serum concentration of the bone resorption marker C-terminal telopeptide of type I collagen (CTX) concentrations did not change in the high-fiber diet group. Bone microCT analysis revealed no changes in trabecular and cortical bone parameters between the high-fiber diet and control groups. Similarly, real-time (RT)-PCR analysis in bone tissue showed no changes in the gene expression of Wnt pathway-related genes (Sost, Dkk-1, Wnt10b, and Lef-1), bone formation markers (Runx2, Col1a1, and Ocn), and inflammatory cytokines (IL-6, IL-8, TNF-α, and IL-10) between the two groups. Our findings suggest that 12-wk high-fiber diet intervention improves metabolic outcomes in patients with T2DM. However, it may reduce bone formation without affecting bone microarchitecture or Wnt pathway regulation. Lay Summary: The development of effective interventions to prevent diabetic bone fragility is crucial. While the benefits of dietary fiber on T2DM have been widely demonstrated, its effect on bone health is still unclear. Thus, we investigated the impact of 12 wk of high-fiber intake on bone in men and women with T2DM. Although we observed improvements in metabolic outcomes, the high-fiber diet also reduced the bone formation marker P1NP in patients with T2DM. However, these changes did not result in alterations in bone microarchitecture or regulation of the Wnt pathway. Graphical Abstract [ABSTRACT FROM AUTHOR]

Discursive transgressions of values widely shared by society or by a certain group of which the declarant is a part are a clearly identifiable and increasingly relevant social phenomenon, also in the academic field. This article has two main objectives. First, it aims to gain new insights into high-complexity public conversations on controversial issues. Second, it seeks to identify the challenges faced by academic institutions in a world where disinformation is perceived as the most significant risk in the near term. This article presents the case of Nobel laureate Sir Tim Hunt and his 'trouble with girls' as a public discourse scandal that triggered both a large critical social response followed by Hunt's expulsion from institutional positions in science, and a subsequent controversy that led to a deterioration of the credibility of the science system in the eyes of society at large. The case has been called 'one of the most extraordinary academic tales of recent years'. Additionally, the article examines a contrasting case: the response of John Finnis and the University of Oxford to calls for the professor's expulsion for allegedly promoting discrimination. For this analysis, the mechanism of sustainable public discourse that manifests a sustainable public positioning in high-complexity contexts will be given special attention since Elizalde's theory of dissent. Analysis and conclusions are discussed. [ABSTRACT FROM AUTHOR]

Background Aims Methods Results Conclusions Inefficient nitrogen (N) use leads to economic losses and environmental harm. Improving N use efficiency (NUE) is crucial. The use of plant biostimulants (PBs), integrated with good agronomic practices, offers a sustainable solution.The study explores the potential use of exhausted cell culture media from plant cell cultures (Nicotiana sp. and Gardenia sp.) as PBs, assessing their role in enhancing plant physiological status and NUE. It also compares their effectiveness against commercial PBs.Two experiments (Experiments 1 and 2) were conducted using cherry tomato plants. In the first one, the two media were applied at different concentrations as a foliar spray to define the optimal dose. This outcome was used to set up Experiment 2, in which both media were compared to commercial PBs under optimal and reduced N supply. Measurements included plant growth, chlorophyll (Chl) content, and NUE indices. Moreover, Experiment 2 examined gene expression related to N assimilation, transport, and response to oxidative stress.Both experiments demonstrated a significant increase in leaf area (≈11%) and aboveground biomass (≈13%) using exhausted media. Furthermore, Experiment 2 demonstrated enhancements in Chl content (≈10%) and plant N accumulation (≈20%). These findings indicate that exhausted media has a comparable efficacy to commercial PBs.The study underscores the practical viability of exhausted cell culture media as effective PBs for tomato growth in both N conditions. This approach aligns with sustainability objectives by repurposing by‐products to enhance plant resilience against abiotic stress and potentially improve the efficiency of N fertilizers. [ABSTRACT FROM AUTHOR]

Noonan syndrome (NS) is an autosomal dominant disorder that varies in severity and can involve multiple organ systems. In approximately 50% of cases, it is caused by missense mutations in the PTPN11 gene (12q24.13). NS is associated with a higher risk of cancer occurrence, specifically hematological disorders. Here, we report a case of a child who was diagnosed at birth with a transient myeloproliferative disorder (TMD). After two years, the child developed hyperdiploid B-cell precursor acute lymphoblastic leukemia (BCP-ALL), receiving a two-year course of treatment. During her continuous complete remission (CCR), a heterozygous germline mutation in the PTPN11 gene [c.218 C>T (p.Thr73lle)] was identified. At the age of ten, the child presented with massive splenomegaly, hyperleukocytosis, and thrombocytopenia, resulting in the diagnosis of juvenile myelomonocytic leukemia (JMML). After an initial response to antimetabolite therapy (6-mercaptopurine), she underwent haploidentical hematopoietic stem cell transplantation (HSCT) and is currently in complete remission. The goal of this review is to gain insight into the various hematological diseases associated with NS, starting from our unique case. [ABSTRACT FROM AUTHOR]

There is no consensus on the optimal management of diabetic foot burn injuries. Here, we systematically identify studies reporting on diabetic foot burns and evaluate outcomes among patients managed operatively vs nonoperatively. PubMed, Embase, and Web of Science were searched. Screening was performed by independent reviewers. Primary research studies with English full texts published between 1980 and 2023 that discussed outcomes of foot burns in adults with diabetes were included and critically appraised using validated tools. Results are presented using descriptive statistics of aggregated data. The search yielded 2402 nonduplicate papers, of which 35 met the inclusion criteria. Nine papers were included for meta-analysis, including 7 retrospective comparative analyses, 1 cross-sectional study, and 1 retrospective chart review. There were 1798 diabetic foot burn patients. The mean age was 58.2 years (SD 4.12), and 73.1% (n = 1314) were male. A total of 15.7% (n = 283) of patients were surgically managed, including debridement (3.7%, n = 66), grafting (8.2%, n = 147), flap (0.2%, n = 3), and primary amputation (7.1%, n = 127). The secondary amputation rate, defined as amputation following initial surgery, was 4.9% (n = 14). The overall amputation rate was 7.8% (n = 141). Other complications included infection (4.0%, n = 72), osteomyelitis (1.9%, n = 34), and graft failure (8.2%, n = 12). One study reported functional status at the last visit. Diabetic foot burns are highly morbid. The surgical management of these complex injuries is high risk, as amputation results in poorer quality of life and functional outcomes. [ABSTRACT FROM AUTHOR]

Recent theoretical conceptualizations of student engagement have raised questions about how to measure student engagement and how engagement varies not only across schools, but also within school and within classrooms. The authors build on existing research on student behavioral engagement and extend this research to emphasize a continuum of disengagement, active engagement, and passive engagement. They review common approaches to measuring engagement and highlight areas where new theoretical conceptualizations of engagement require new approaches to measurement. The authors analyze how student behavioral engagement changed depending on the context and demonstrate the need of a finer scale of engagement. They find there was not a uniform association of higher behavioral engagement and student interaction with peers, but it was the interaction with other students and the teacher that was predictive of increased engagement. Their work suggests that disaggregating behavioral engagement into disengagement, active engagement, and passive engagement has important research and conceptual implications. [At time of submission to ERIC this article was in press with "The Journal of Educational Research."]

Short QT syndrome (SQTS) is an inherited cardiac ion-channel disease related to an increased risk of sudden cardiac death (SCD) in young and otherwise healthy individuals. SCD is often the first clinical presentation in patients with SQTS. However, arrhythmia risk stratification is presently unsatisfactory in asymptomatic patients. In this context, artificial intelligence-based electrocardiogram (ECG) analysis has never been applied to refine risk stratification in patients with SQTS. The purpose of this study was to analyze ECGs from SQTS patients with the aid of different AI algorithms to evaluate their ability to discriminate between subjects with and without documented life-threatening arrhythmic events. The study group included 104 SQTS patients, 37 of whom had a documented major arrhythmic event at presentation and/or during follow-up. Thirteen ECG features were measured independently by three expert cardiologists; then, the dataset was randomly divided into three subsets (training, validation, and testing). Five shallow neural networks were trained, validated, and tested to predict subject-specific class (non-event/event) using different subsets of ECG features. Additionally, several deep learning and machine learning algorithms, such as Vision Transformer, Swin Transformer, MobileNetV3, EfficientNetV2, ConvNextTiny, Capsule Networks, and logistic regression were trained, validated, and tested directly on the scanned ECG images, without any manual feature extraction. Furthermore, a shallow neural network, a 1-D transformer classifier, and a 1-D CNN were trained, validated, and tested on ECG signals extracted from the aforementioned scanned images. Classification metrics were evaluated by means of sensitivity, specificity, positive and negative predictive values, accuracy, and area under the curve. Results prove that artificial intelligence can help clinicians in better stratifying risk of arrhythmia in patients with SQTS. In particular, shallow neural networks’ processing features showed the best performance in identifying patients that will not suffer from a potentially lethal event. This could pave the way for refined ECG-based risk stratification in this group of patients, potentially helping in saving the lives of young and otherwise healthy individuals.

Vascular calcification (VC) is a common complication in patients with chronic kidney disease which increases their mortality. Although oxidative stress is involved in the onset and progression of this disorder, the specific role of some of the main redox regulators, such as catalase, the main scavenger of H2O2, remains unclear. In the present study, epigastric arteries of kidney transplant recipients, a rat model of VC, and an in vitro model of VC exhibiting catalase (Cts) overexpression were analysed. Pericalcified areas of human epigastric arteries had increased levels of catalase and cytoplasmic, rather than nuclear runt-related transcription factor 2 (RUNX2). In the rat model, advanced aortic VC concurred with lower levels of the H2O2-scavenger glutathione peroxidase 3 compared to controls. In an early model of calcification using vascular smooth muscle cells (VSMCs), Cts VSMCs showed the expected increase in total levels of RUNX2. However, Cts VMSCs also exhibited a lower percentage of the nucleus stained for RUNX2 in response to calcifying media. In this early model of VC, we did not observe a dysregulation of the mitochondrial redox state; instead, an increase in the general redox state was observed in the cytoplasm. These results highlight the complex role of antioxidant enzymes as catalase by regulation of RUNX2 subcellular location delaying the onset of VC.

Nowadays, the study and digitization of historical, architectural, and archaeological heritage are extremely important, covering the creation of digital twins—virtual replicas of real spaces and environments. Such reconstructions can be achieved using technologies with passive or active light sensors: laser scanners as light emitters, or photogrammetry through the creation of photographic images. As for the latter case, a distinction must be made between terrestrial and aerial shots, increasingly facilitated by the spread of UAV systems. Point clouds are aligned using georeferenced points measured with a total station. To create a faithful virtual model of the subjects, dense point clouds from a laser scanner are used to generate meshes, which are textured in high resolution from aerial and terrestrial photographs. All techniques can be integrated with each other, as demonstrated through the experiences of two case studies, each serving different purposes. The first is a detailed survey conducted for CAD representation of certain areas of Rocca Farnese in Capodimonte. The second is an instrumental survey for the creation of a realistic digital twin, aimed at providing an immersive VR experience of the archaeological area of Santa Croce in Gerusalemme in Rome.

Volcano monitoring is the key approach in mitigating the risks associated with volcanic phenomena. Although Antarctic volcanoes are characterized by remoteness, the 2010 Eyjafjallajökull eruption and the 2022 Hunga eruption have reminded us that even the farthest and/or least-known volcanoes can pose significant hazards to large and distant communities. Hence, it is important to also develop monitoring systems in the Antarctic volcanoes, which involves installing and maintaining multiparametric instrument networks. These tasks are particularly challenging in polar regions as the instruments have to face the most extreme climate on the Earth, characterized by very low temperatures and strong winds. In this work, we describe the multiparametric monitoring system recently deployed on the Melbourne volcano (Victoria Land, Antarctica), consisting of seismic, geochemical and thermal sensors together with powering, transmission and acquisition systems. Particular strategies have been applied to make the monitoring stations efficient despite the extreme weather conditions. Fumarolic ice caves, located on the summit area of the Melbourne volcano, were chosen as installation sites as they are protected places where no storm can damage the instruments and temperatures are close to 0 °C all year round. In addition, the choice of instruments and their operating mode has also been driven by the necessity to reduce energy consumption. Indeed, one of the most complicated tasks in Antarctica is powering a remote instrument year-round. The technological solutions found to implement the monitoring system of the Melbourne volcano and described in this work can help create volcano monitoring infrastructures in other polar environments.

Teacher labor markets are evolving across the United States. The rise of charter schools, alternative teacher certification, and portfolio districts are transforming teachers' access to employment, changing the way they search for and apply for jobs, and may also change the role that social networks play in the job search. However, we know little about how teachers use their networks to find jobs, particularly in increasingly fragmented local labor markets. We draw on interviews with 127 teachers in three districts chosen to reflect an increasing presence of charter schools: New Orleans, Detroit, and San Antonio. We find that the extent of fragmentation in a city's labor market drives the use of networks, with important implications for job access and equity.

Background: Substantial research on reform implementation highlights numerous challenges to implementing innovations at scale with depth and sustainability, yet new reforms continue to encounter many of the same challenges. This has led to calls for researchers to work in partnership with practitioners to design, implement, and scale educational innovations. Although these approaches hold promise, little is known about the internal operations of these improvement approaches and the experiences of their participants. Purpose: Through a case study of a research-practice partnership that uses a continuous improvement approach to design and development, this article explores how the collaborative design process shaped the resulting innovation design. Research Design: This is a qualitative case study that included interviews with members of the district and school design teams, observations and field notes from design team meetings, and participant feedback forms. Findings/Results: The evidence converges on three main challenges in the design process. These challenges point to tensions in maximizing all the design factors because they sometimes conflicted with each other: (1) Members were most engaged when the work was very specific and deemed feasible in a particular context, (2) Efforts to develop more specificity in the design emphasis were limited by efforts to engage educators in a collaborative process in which school-level actors had ownership over key design decisions, and (3) The abstractness of the emerging reform led to difficulties in establishing a shared deep understanding of each core component of the reform. Finally, the ability of school teams to productively resolve these tensions was related to the existing capacity of the school. Conclusions: This case study of a collaborative design process in a research-practice partnership illustrates the complexities of the co-construction of a set of reform practices between researchers, practitioners, and other stakeholders and highlights the need for a delicate balance between specificity of the design and local engagement. We showed how a collaborative process fostered high engagement as researchers and practitioners co-constructed the reform, and how the team struggled to define the core strategies in sufficient detail to allow for implementation planning in a way that maintained the co-constructed design. There appeared to be a tension between achieving the necessary concreteness or specificity in the reform design that would be implemented across contexts, and a process that valued local ownership and collaborative decision-making.

Abstract Background Vitamin D status has been implicated in COVID-19 disease. The objective of the COVID-VIT-D trial was to investigate if an oral bolus of cholecalciferol (100,000 IU) administered at hospital admission influences the outcomes of moderate-severe COVID-19 disease. In the same cohort, the association between baseline serum calcidiol levels with the same outcomes was also analysed. Methods The COVID-VIT-D is a multicentre, international, randomised, open label, clinical trial conducted throughout 1 year. Patients older than 18 years with moderate-severe COVID-19 disease requiring hospitalisation were included. At admission, patients were randomised 1:1 to receive a single oral bolus of cholecalciferol (n=274) or nothing (n=269). Patients were followed from admission to discharge or death. Length of hospitalisation, admission to intensive care unit (ICU) and mortality were assessed. Results In the randomised trial, comorbidities, biomarkers, symptoms and drugs used did not differ between groups. Median serum calcidiol in the cholecalciferol and control groups were 17.0 vs. 16.1 ng/mL at admission and 29.0 vs. 16.4 ng/mL at discharge, respectively. The median length of hospitalisation (10.0 [95%CI 9.0–10.5] vs. 9.5 [95%CI 9.0–10.5] days), admission to ICU (17.2% [95%CI 13.0–22.3] vs. 16.4% [95%CI 12.3–21.4]) and death rate (8.0% [95%CI 5.2–12.1] vs. 5.6% [95%CI 3.3–9.2]) did not differ between the cholecalciferol and control group. In the cohort analyses, the highest serum calcidiol category at admission (>25ng/mL) was associated with lower percentage of pulmonary involvement and better outcomes. Conclusions The randomised clinical trial showed the administration of an oral bolus of 100,000 IU of cholecalciferol at hospital admission did not improve the outcomes of the COVID-19 disease. A cohort analysis showed that serum calcidiol at hospital admission was associated with outcomes. Trial registration COVID-VIT-D trial was authorised by the Spanish Agency for Medicines and Health products (AEMPS) and registered in European Union Drug Regulating Authorities Clinical Trials (EudraCT 2020-002274-28) and in ClinicalTrials.gov ( NCT04552951 ).

Coronavirus disease (COVID-19) was confirmed as a pandemic disease on February 11, 2020. The pandemic has already caused thousands of victims and infected several million people around the world. The aim of this work is to provide a Covid-19 infection screening tool. Currently, the most widely used clinical tool for detecting the presence of infection is the reverse transcription polymerase chain reaction (RT-PCR), which is expensive, less sensitive and requires the resource of specialized medical personnel. The use of X-ray images represents one of the latest challenges for the rapid diagnosis of the Covid-19 infection. This work involves the use of advanced artificial intelligence techniques for diagnosis using algorithms for classification purposes. The goal is to provide an automatic infection detection method while maximizing detection accuracy. A public database was used which includes images of COVID-19 patients, patients with viral pneumonia, patients with pulmonary opacity, and healthy patients. The methodology used in this study is based on transfer learning of pre-trained networks to alleviate the complexity of calculation. In particular, three different types of convolutional neural networks, namely, InceptionV3, ResNet50 and Xception, and the Vision Transformer are implemented. Experimental results show that the Vision Transformer outperforms convolutional architectures with a test accuracy of 99.3% vs 85.58% for ResNet50 (best among CNNs). Moreover, it is able to correctly distinguish among four different classes of chest X-ray images, whereas similar works only stop at three categories at most. The high accuracy of this computer-assisted diagnostic tool can significantly improve the speed and accuracy of COVID-19 diagnosis.

Introduction: Adipose tissue is widely exploited in regenerative medicine thanks to its trophic properties, mainly based on the presence of adipose-derived stromal cells. Numerous devices have been developed to promote its clinical use, leading to the introduction of one-step surgical procedures to obtain minimally manipulated adipose tissue derivatives. However, only a few studies compared their biological properties. This study aimed to characterize micro-fragmented (MAT) and nanofat adipose tissue (NAT) obtained with two different techniques.Methods: MAT, NAT and unprocessed lipoaspirate were collected from surgical specimens. RNA extraction and collagenase isolation of stromal vascular fraction (SVF) were performed. Tissue sections were analysed by histological and immunohistochemical (collagen type I, CD31, CD34 and PCNA) staining to assess tissue morphology and cell content. qPCR was performed to evaluate the expression of stemness-related (SOX2, NANOG and OCT3/4), extracellular matrix (COL1A1) and inflammatory genes (IL1β, IL6 and iNOS). Furthermore, multilineage differentiation was assessed following culture in adipogenic and osteogenic media and staining with Oil Red O and Alizarin red. ASC immunophenotype was assessed by flow cytometric analysis of CD90, CD105, CD73 and CD45.Results: Histological and immunohistochemical results showed an increased amount of stroma and a reduction of adipocytes in MAT and NAT, with the latter displaying the highest content of collagen type I, CD31, CD34 and PCNA. From LA to MAT and NAT, an increasing expression of NANOG, SOX2, OCT3/4, COL1A1 and IL6 was noted, while no significant differences in terms of IL1β and iNOS emerged. No statistically significant differences were noted between NAT and SVF in terms of stemness-related genes, while the latter demonstrated a significantly higher expression of stress-related markers. SVF cells derived from all three samples (LA, MAT, and NAT) showed a similar ASC immunoprofile as well as osteogenic and adipogenic differentiation.Discussion: Our results showed that both MAT and NAT techniques allowed the rapid isolation of ASC-rich grafts with a high anabolic and proliferative potential. However, NAT showed the highest levels of extracellular matrix content, replicating cells, and stemness gene expression. These results may provide precious clues for the use of adipose tissue derivatives in the clinical setting.