Hyperpolarizability and operational magic wavelength in an optical lattice clock

Optical clocks benefit from tight atomic confinement enabling extended interrogation times as well as Doppler- and recoil-free operation. However, these benefits come at the cost of frequency shifts that, if not properly controlled, may degrade clock accuracy. Numerous theoretical studies have predicted optical lattice clock frequency shifts that scale nonlinearly with trap depth. To experimentally observe and constrain these shifts in an $^{171}$Yb optical lattice clock, we construct a lattice enhancement cavity that exaggerates the light shifts. We observe an atomic temperature that is proportional to the optical trap depth, fundamentally altering the scaling of trap-induced light shifts and simplifying their parametrization. We identify an "operational" magic wavelength where frequency shifts are insensitive to changes in trap depth. These measurements and scaling analysis constitute an essential systematic characterization for clock operation at the $10^{-18}$ level and beyond.Comment: 5 + 2 pages, 3 figures, added supplementa

A dedicated protocol and environment for central venous catheter removal in pediatric patients affected by oncohematological diseases

The removal of long-term central venous catheters (CVCs) is not performed according to evidence-based guidelines, thus conveying the message that it is a procedure of secondary importance. Our study aims at comparing the experience at Bambino Gesù Pediatric Hospital before and after the implementation of a dedicated protocol and the identification of a specific area to perform such a procedure under the so-called nonoperating room anesthesia (NORA)

Experimental investigation of the effect of high pressure nozzle geometry on spray characteristics

Phase Doppler Anemometry (PDA) measurements [1] are applied to low length to diameter ratio (L/D) multi-hole nozzles operating with at high fuel pressure (20 MPa) that are implemented in the new Euro6 generation of Gasoline Direct Injection engines. For these multi-jets spray, the authors intend to demonstrate; the importance of the spray shape, the effect of hole design and the reorganisation dynamic of the drop size distribution by turbulent mixing. To do so, we report significant experimental effort along with careful data reduction, exercised to understand the spray behaviour, in particular separating the sources of experimental uncertainty from the flow physics. A practical methodology is adopted as a compromise between measurement effort, error removal, and the need to understand underlying physical processes within the spray plume. The present work focuses mostly on the drop size and velocity profiles (two-component) perpendicular to the plume direction

Sudden olfactory loss as an early marker of COVID-19: a nationwide Italian survey

Purpose: The presence of many asymptomatic COVID-19 cases may increase the risks of disease dissemination, mainly for physicians. There are numerous reports on the frequent findings of sudden anosmia or hyposmia, before or at the same time of the typical COVID-19 symptoms onset. The aim of this study was to verify the association of olfactory impairment and COVID-19, providing a basis for subsequent research in the field of COVID-19 clinical heterogeneity. Methods: We developed a 15-item online questionnaire on “Sudden Olfactory Loss (SOL) and COVID-19” that was administered during March 2020 to Italian general practitioners registered to a social media group. Results: One hundred and eighty responses were received. SOL was identified as a significant sign of infection in COVID-19 patients, mainly aged between 30 and 40 years, even in the absence of other symptoms. SOL was present as an initial symptom in 46.7% of subjects, and in 16.7%, it was the only symptom. Among the COVID-19 confirmed cases, SOL occurred as the only symptom in 19.2% of patients. Conclusion: SOL could represent a possible early symptom in otherwise asymptomatic COVID-19 subjects. Subjects affected by SOL should be considered as potential COVID-19 cases. Level of evidence: 4

Tinnitus and equilibrium disorders in COVID-19 patients: preliminary results

Purpose: Tinnitus and equilibrium disorders such as dizziness and vertigo have been reported by patients with COVID-19; however, they have been rarely investigated. The aim of this study was to study the prevalence of subjective tinnitus and dizziness in a sample of COVID-19 patients using an online 10-item close-ended questionnaire. Methods: A multicentric study that included 15 Italian hospitals in different regions was conducted using an online 10-item close-ended questionnaire developed to identify the presence of tinnitus and balance disorders in patients with COVID-19 between May 5 and June 10, 2020. The questionnaire was administered to 185 patients in a period of > 30 – < 60 days after diagnosis of COVID-19; responses were recorded in an online Excel spreadsheet. The questionnaire was composed of three sections: (1) demographic information; (2) presence and characteristics of tinnitus and dizziness after COVID-19 diagnosis; (3) possible association with migraine. Results: Thirty-four patients (18.4%) reported equilibrium disorders after COVID-19 diagnosis. Of these, 32 patients reported dizziness (94.1%) and 2 (5.9%) reported acute vertigo attacks. Forty-three patients (23.2%) reported tinnitus; 14 (7.6%) reported both tinnitus and equilibrium disorders. Conclusion: This study suggests that the presence of subjective otoneurological symptoms such as tinnitus and balance disorders can affect COVID-19 patients; further studies are necessary to investigate the prevalence and pathophysiological mechanisms underlying these subjective symptoms in COVID-19 patients

How a Clinical Trial Unit can improve independent clinical research in rare tumors: the Italian Sarcoma Group experience

Background: The Italian Sarcoma Group (ISG) is a nonprofit group of professionals established in 1997 aimed to improve the quality of care and promote the independent research in sarcomas. The increased regulatory requirements, the chance to increase the number of trials with other cooperative groups and an interest from pharmaceutical companies in supporting independent research, generated the need of an internal service for research management. Methods and results: In 2010, ISG implemented in its organization a Clinical Trial Unit (CTU). The CTU was appointed to fully manage Clinical Trial Operations, to guarantee regulation compliance and provide a central support to the investigators, fostering a collaboration both at national and international level. In 2016 ISG promoted 25 studies in about 120 centers, with a fivefold increase in the last 5 years: 68% were interventional and 32% observational. Nine of the 17 interventional studies (52%) were supported by pharmaceutical companies, while 4 (24%) were funded by European Commission within specific projects on sarcomas and 4 (24%) were supported by the ISG itself. Conclusion: The contribution of ISG researchers to the international community was striking from the earliest years of the ISG creation. The challenges of the regulatory clinical research scenario, which imposes solid and hard-fast methodology with deep knowledge and expertise, highlighted the need to identify qualified and dedicated experts able to run and follow the multifaceted aspects of trials. Our analysis demonstrated how this model has led to a growth in competitiveness of the group. The collaboration between clinicians and CTU made possible to support the research with high scientific and ethical standards and to increase the number of trials, sites and overall enrolled patients. The reduced time for approvals, the continuous support to sites, the increased speed in data collection and analysis make the ISG research attractive for pharmaceutical industries, despite the problems that have characterized the independent research in the last years. The ability to fully manage and oversight Clinical Operations and the high quality of delivered services, have led the ISG to be recognized as a reliable partner and coordinator within the international sarcoma networks

Detection of maturity and ligament injury using magic angle directional imaging

Purpose: To investigate whether magnetic field–related anisotropies of collagen may be correlated with postmortem findings in animal models. Methods: Optimized scan planning and new MRI data‐processing methods were proposed and analyzed using Monte Carlo simulations. Six caprine and 10 canine knees were scanned at various orientations to the main magnetic field. Image intensities in segmented voxels were used to compute the orientation vectors of the collagen fibers. Vector field and tractography plots were computed. The Alignment Index was defined as a measure of orientation distribution. The knees were subsequently assessed by a specialist orthopedic veterinarian, who gave a pathological diagnosis after having dissected and photographed the joints. Results: Using 50% less scans than reported previously can lead to robust calculation of fiber orientations in the presence of noise, with much higher accuracy. The 6 caprine knees were found to range from very immature ( 3 years). Mature specimens exhibited significantly more aligned collagen fibers in their patella tendons compared with the immature ones. In 2 of the 10 canine knees scanned, partial cranial caudal ligament tears were identified from MRI and subsequently confirmed with encouragingly high consistency of tractography, Alignment Index, and dissection results. Conclusion: This method can be used to detect injury such as partial ligament tears, and to visualize maturity‐related changes in the collagen structure of tendons. It can provide the basis for new, noninvasive diagnostic tools in combination with new scanner configurations that allow less‐restricted field orientations

Clusters of Basic Amino Acids Contribute to RNA Binding and Nucleolar Localization of Ribosomal Protein L22

The ribosomal protein L22 is a component of the 60S eukaryotic ribosomal subunit. As an RNA-binding protein, it has been shown to interact with both cellular and viral RNAs including 28S rRNA and the Epstein-Barr virus encoded RNA, EBER-1. L22 is localized to the cell nucleus where it accumulates in nucleoli. Although previous studies demonstrated that a specific amino acid sequence is required for nucleolar localization, the RNA-binding domain has not been identified. Here, we investigated the hypothesis that the nucleolar accumulation of L22 is linked to its ability to bind RNA. To address this hypothesis, mutated L22 proteins were generated to assess the contribution of specific amino acids to RNA binding and protein localization. Using RNA-protein binding assays, we demonstrate that basic amino acids 80–93 are required for high affinity binding of 28S rRNA and EBER-1 by L22. Fluorescence localization studies using GFP-tagged mutated L22 proteins further reveal that basic amino acids 80–93 are critical for nucleolar accumulation and for incorporation into ribosomes. Our data support the growing consensus that the nucleolar accumulation of ribosomal proteins may not be mediated by a defined localization signal, but rather by specific interaction with established nucleolar components such as rRNA