Flow curvature effects on dynamic behaviour of a novel vertical axis tidal current turbine: numerical and experimental analysis

The paper deals with performances analysis of vertical axis turbine to exploit tidal marine currents. Flow curvature effects on performences of a novel vertical axis turbine have been investuigated. It has been shown that the flow curvature effect allows to design properly an accurate airfoil shape to increase turbine performances

Beam diagnostics for charge and position measurements in ELI-NP GBS

The advanced source of Gamma-ray photons to be built in Bucharest (Romania), as part of the ELI-NP European Research Infrastructure, will generate photons by Compton back-scattering in the collision between a multi-bunch electron beam and a high intensity recirculated laser pulse. An S-Band photoinjector and the following C-band Linac at a maximum energy of 720MeV, under construction by an European consortium (EurogammaS) led by INFN, will operate at 100Hz repetition rate with trains of 32 electron bunches, separated by 16ns and a 250pC nominal charge. The different BPMs and current transformers used to measure transverse beam position and charge along the LINAC are described. Design criteria, production status and bench test results of the charge and position pickups are reported in the paper, together with the related data acquisition systems

Dynamic behavior of novel vertical axis tidal current turbine: numerical and experimental investigations

This paper presents a summary of the recent work done by the authors regarding the design, construction and test of a novel patented vertical axis and variable pitching blade hydro turbine, named KOBOLD, capable of harnessing clean and renewable energy from marine tidal currents. The KOBOLDturbine, currently moored in Messina Strait, between mainland Italy and Sicily island, is the only existing turbine of this type devoted to exploit tidal currents, and has a 25% global system efficiency. Theoretical analysis and numerical prediction performanceshave been compared and validated with experimental test results on both model and real scale turbines. Moreover, the recent activities in terms of numerical and experimental investigations on vertical axis hydro turbines are presente

Dynamic Behaviour of the Patented Kobold Tidal Current Turbine: Numerical and Experimental Aspects

This paper provides a summary of the work done at DPA on numerical and experimental investigations of a novel patented vertical axis and variable pitching blades hydro turbine designed to harness energy from marine tidal currents. Ponte di Archimede S.p.A. Company, located in Messina, Italy, owns the patented KOBOLD turbine that is moored in the Messina Strait, between the mainland and Sicily. The turbine has a rotor with a diameter of 6 meters, three vertical blades of 5 meters span with a 0.4 m chord ad hoc designed curved airfoil, producing high lift with no cavitation. The rated power is 160 kW with 3.5 m/s current speed, which means 25% global system efficiency. The VAWT and VAWT_DYN computer codes, based on Double Multiple Steamtube, have been developed to predict the steady and dynamic performances of a cycloturbine with fixed or self-acting variable pitch straight-blades. A theoretical analysis and a numerical prediction of the turbine performances as well as experimental test results on both a model and the real scale turbine will be presented and discussed.

Post-stroke depression increases disability more than 15% in ischemic stroke survivors: a case-control study

We performed a retrospective, case-control study in consecutive ischemic stroke patients admitted to our stroke rehabilitation unit. Patients were matched for severity of neurological impairment (evaluated with the Canadian Neurological Scale, CNS), age (difference within 1 year), and onset admission interval (difference within 3 days). Participants were divided into two subgroups according to the presence or absence of PSD. Aim was to assess the specific influence of post-stroke depression (PSD) and antidepressant treatment on both basal functional status and rehabilitation outcomes. All PSD patients were treated primarily with serotoninergic antidepressants (AD). The final sample included 280 patients with depression (out of 320 found in a whole case series of 993 ischemic patients, i.e., 32.25%) and 280 without depression. Forty patients with depression were excluded because they had a history of severe psychiatric illness or aphasia, with a severe comprehension deficit. On one hand, PSD patients obtained lower Barthel Index (BI) and Rivermead Mobility Index (RMI) scores at both admission and discharge, with minor effectiveness of rehabilitative treatment and longer length of stay; on the other hand, this group had a lower percentage of dropouts. Lastly, PSD patients showed a different functional outcome, based on their response to antidepressant therapy, that was significantly better in responders than in non-responders (13.13%). Our results confirm the unfavorable influence of PSD on functional outcome, despite pharmacological treatment

Colonic metastasis from breast carcinoma detection by CESM and PET/CT: A case report

Introduction: Metastatic spread in invasive lobular carcinoma (ILC) of breast mainly occurs in bones, gynecological organs, peritoneum, retroperitoneum, and gastrointestinal (GI) tract. Metastases to the GI tract may arise many years after initial diagnosis and can affect the tract from the tongue to the anus, stomach being the most commonly involved site. Clinical presentations are predominantly nonspecific, and rarely asymptomatic. CEA, CA 15-3, and CA 19-9 may be informative for symptomatic patients who have had a previous history of breast cancer. Case presentation: We introduce the case of asymptomatic colonic metastasis from breast carcinoma in a 67-year-old woman followed-up for Luminal A ILC. Diagnosis was performed through positron emission tomography/computed tomography (PET/CT) scan and contrast-enhancement spectral mammography (CESM), steering endoscopist to spot the involved intestinal tract and in ruling out further dissemination in the breast parenchyma. Conclusion: In colonic metastases, tumor markers might not be totally reliable. In asymptomatic cases, clinical conditions might be underappreciated, missing local or distant recurrence. CT and PET/CT scan might be useful in diagnosing small volume diseases, and steering endoscopist toward GI metastasis originating from the breast. CESM represents a tolerable and feasible tool that rules out multicentricity and multifocality of breast localization. Moreover, particular patients could tolerate it better than magnetic resonance imaging (MRI)

Effects of Walking Endurance Reduction on Gait Stability in Patients with Stroke

Control of gait is usually altered following stroke, and it may be further compromised by overexertion and fatigue. This study aims to quantitatively assess patients' gait stability during six-minute walking, measuring upper body accelerations of twenty patients with stroke (64 ± 13 years old) and ten age-matched healthy subjects (63 ± 10 years old). Healthy subjects showed a steady gait in terms of speed and accelerations over the six minutes. Conversely, the patients unable to complete the test (n = 8) progressively reduced their walking speed (−22 ± 11%, confidence interval CI95%: −13, −29%, P = 0.046). Patients able to complete the test (n = 12) did not vary their walking speed over time (P = 0.493). However, this ability was not supported by an adequate capacity to maintain their gait stability, as shown by a progressive increase of their upper body accelerations (+5 ± 11%, CI95%: −1; +12%, P = 0.010). Walking endurance and gait stability should be both quantitatively assessed and carefully improved during the rehabilitation of patients with stroke

Accuracy and reproducibility of contrast-enhanced mammography in the assessment of response to neoadjuvant chemotherapy in breast cancer patients with calcifications in the tumor bed

This study aimed to evaluate contrast-enhanced mammography (CEM) accuracy and reproducibility in the detection and measurement of residual tumor after neoadjuvant chemotherapy (NAC) in breast cancer (BC) patients with calcifications, using surgical specimen pathology as the reference. Pre-and post-NAC CEM images of 36 consecutive BC patients receiving NAC in 2012–2020, with calcifications in the tumor bed at diagnosis, were retrospectively reviewed by two radiologists; described were absence/presence and size of residual disease based on contrast enhancement (CE) only and CE plus calcifications. Twenty-eight patients (77.8%) had invasive and 5 (13.9%) in situ-only residual disease at surgical specimen pathology. Considering CE plus calcifications instead of CE only, CEM sensitivity for invasive residual tumor increased from 85.7% (95% CI = 67.3–96%) to 96.4% (95% CI = 81.7–99.9% ) and specificity decreased from 5/8 (62.5%; 95% CI = 24.5–91.5%) to 1/8 (14.3%; 95% CI = 0.4–57.9%). For in situ-only residual disease, false negatives decreased from 3 to 0 and false positives increased from 1 to 2. CEM pathology concordance in residual disease measurement increased (R squared from 0.38 to 0.45); inter-reader concordance decreased (R squared from 0.79 to 0.66). Considering CE plus calcifications to evaluate NAC response in BC patients increases sensitivity in detection and accuracy in measurement of residual disease but increases false positives

Biomarkers changes after neoadjuvant chemotherapy in breast cancer: A seven-year single institution experience

The adoption of neoadjuvant chemotherapy (NACT) for breast cancer (BC) is increasing. The need to repeat the biomarkers on a residual tumor after NACT is still a matter of debate. We verified estrogen receptors (ER), progesterone receptors (PR), Ki67 and human epidermal growth factor receptor 2 (HER2) status changes impact in a retrospective monocentric series of 265 BCs undergoing NACT. All biomarkers changed with an overall tendency toward a reduced expression. Changes in PR and Ki67 were statistically significant (p = 0.001). Ki67 changed in 114/265 (43.0%) cases, PR in 44/265 (16.6%), ER in 31/265 (11.7%) and HER2 in 26/265 (9.8%). Overall, intrinsic subtype changed in 72/265 (27.2%) cases after NACT, and 10/265 (3.8%) cases switched to a different adjuvant therapy accordingly. Luminal subtypes changed most frequently (66/175; 31.7%) but with less impact on therapy (5/175; 2.8%). Only 3 of 58 triple-negative BCs (5.2%) changed their intrinsic subtype, but all of them switched treatment. No correlation was found between intrinsic subtype changes and clinicopathological features. To conclude, biomarkers changes with prognostic implications occurred in all BC intrinsic subtypes, albeit they impacted therapy mostly in HER2 negative and/or hormone receptors negative BCs. Biomarkers retesting after NACT is important to improve both tailored adjuvant therapies and prognostication of patients

Temperature analysis in the shock waves regime for gas-filled plasma capillaries in plasma-based accelerators

Plasma confinement represents a crucial point for plasma-based accelerators and plasma lenses because it can strongly affect the beam properties. For this reason, an accurate measurement of the plasma parameters, as plasma temperature, pressure and electron density, must be performed. In this paper, we introduce a novel method to detect the plasma temperature and the pressure for gas-filled capillaries in use at the SPARC-LAB test facility. The proposed method is based on the shock waves produced at the ends of the capillary during the gas discharge and the subsequent plasma formation inside it. By measuring the supersonic speed of the plasma outflow, the thermodynamic parameters have been obtained both outside and inside the capillary. A plasma temperature around 1.4 eV has been measured, that depends on the geometric properties and the operating conditions of the capillary