The action of Volterra integral operators with highly singular kernels on H\"older continuous, Lebesgue and Sobolev functions

For kernels $\nu$ which are positive and integrable we show that the operator $g\mapsto J_\nu g=\int_0^x \nu(x-s)g(s)ds$ on a finite time interval enjoys a regularizing effect when applied to H\"older continuous and Lebesgue functions and a "contractive" effect when applied to Sobolev functions. For H\"older continuous functions, we establish that the improvement of the regularity of the modulus of continuity is given by the integral of the kernel, namely by the factor $N(x)=\int_0^x \nu(s)ds$. For functions in Lebesgue spaces, we prove that an improvement always exists, and it can be expressed in terms of Orlicz integrability. Finally, for functions in Sobolev spaces, we show that the operator $J_\nu$ "shrinks" the norm of the argument by a factor that, as in the H\"older case, depends on the function $N$ (whereas no regularization result can be obtained). These results can be applied, for instance, to Abel kernels and to the Volterra function $\mathcal{I}(x) = \mu(x,0,-1) = \int_{0}^{\infty}x^{s-1}/\Gamma(s)\,ds$, the latter being relevant for instance in the analysis of the Schr\"odinger equation with concentrated nonlinearities in $\mathbb{R}^{2}$.Comment: 27 pages, 3 figure

AIRO Breast Cancer Group Best Clinical Practice 2022 Update

Introduction: Breast cancer is the most common tumor in women and represents the leading cause of cancer death. Radiation therapy plays a key-role in the treatment of all breast cancer stages. Therefore, the adoption of evidence-based treatments is warranted, to ensure equity of access and standardization of care in clinical practice.Method: This national document on the highest evidence-based available data was developed and endorsed by the Italian Association of Radiation and Clinical Oncology (AIRO) Breast Cancer Group.We analyzed literature data regarding breast radiation therapy, using the SIGN (Scottish Intercollegiate Guidelines Network) methodology (www.sign.ac.uk). Updated findings from the literature were examined, including the highest levels of evidence (meta-analyses, randomized trials, and international guidelines) with a significant impact on clinical practice. The document deals with the role of radiation therapy in the treatment of primary breast cancer, local relapse, and metastatic disease, with focus on diagnosis, staging, local and systemic therapies, and follow up. Information is given on indications, techniques, total doses, and fractionations.Results: An extensive literature review from 2013 to 2021 was performed. The work was organized according to a general index of different topics and most chapters included individual questions and, when possible, synoptic and summary tables. Indications for radiation therapy in breast cancer were examined and integrated with other oncological treatments. A total of 50 questions were analyzed and answered.Four large areas of interest were investigated: (1) general strategy (multidisciplinary approach, contraindications, preliminary assessments, staging and management of patients with electronic devices); (2) systemic therapy (primary, adjuvant, in metastatic setting); (3) clinical aspects (invasive, non-invasive and micro-invasive carcinoma; particular situations such as young and elderly patients, breast cancer in males and cancer during pregnancy; follow up with possible acute and late toxicities; loco-regional relapse and metastatic disease); (4) technical aspects (radiation after conservative surgery or mastectomy, indications for boost, lymph node radiotherapy and partial breast irradiation).Appendixes about tumor bed boost and breast and lymph nodes contouring were implemented, including a dedicated web application. The scientific work was reviewed and validated by an expert group of breast cancer key-opinion leaders.Conclusions: Optimal breast cancer management requires a multidisciplinary approach sharing therapeutic strategies with the other involved specialists and the patient, within a coordinated and dedicated clinical path. In recent years, the high-level quality radiation therapy has shown a significant impact on local control and survival of breast cancer patients. Therefore, it is necessary to offer and guarantee accurate treatments according to the best standards of evidence-based medicine

“Health Comes First”: Action Tendencies to Health-Related Stimuli in People with Health-Anxiety as Revealed by an Emotional Go/No-Go Task

The processing of health-related stimuli can be biased by health anxiety and anxiety sensitivity but, at the moment, it is far from clear whether health-related stimuli can affect motor readiness or the ability to inhibit action. In this preliminary study, we assessed whether different levels of health anxiety and anxiety sensitivity affect disposition to action in response to positive and negative health-related stimuli in non-clinical individuals. An emotional go/no-go task was devised to test action disposition in response to positive (wellness-related), and negative (disease-related) stimuli in non-clinical participants who also underwent well-validated self-report measures of health anxiety and anxiety sensitivity. The main results showed that both health anxiety and anxiety sensitivity biased participants’ responses. Importantly, safety-seeking and avoidance behaviors differently affected action disposition in response to positive and negative stimuli. These preliminary results support the idea that health anxiety and anxiety sensitivity could determine a hypervigilance for health-related information with a different perturbation of response control depending on the valence of the stimuli. Health anxiety and health anxiety disorder do form a continuum; thus, capturing different action tendencies to health-related stimuli could represent a valuable complementary tool to detect processing biases in persons who might develop a clinical condition

Development of the New Kibou\uae Equipment for Continuous Renal Replacement Therapy from Scratch to the Final Configuration

A new technology has recently appeared in the area of extracorporeal therapies for critically ill patients with acute kidney injury. The International Renal Research Institute of Vicenza was involved from the beginning in the development of a new continuous renal replacement therapy (CRRT) equipment with peculiar characteristics. We report the overall experience from design of the new machine to its in vitro and in vivo testing. Kibou\uae (Asahi Kasei Kuraray Medical Co., Ltd., Tokyo, Japan) is a new multifunctional machine designed for delivering RRT. Kibou\uae carries out many features of the fourth generation CRRT machines including the possibility of a dynamic prescription and reduction of nursing workload. We describe our first experience with this new device, focusing on several usability and performance parameters. A specific in vitro protocol was designed to analyze the various characteristics and accuracy of performance of the machine. Furthermore, a preliminary in vivo alpha trial with 12 CRRT sessions was performed to test, characterize and evaluate the machine in terms of usability, flexibility and reliability. The in vitro evaluation confirmed an adequate design and a good usability of the machine with accurate delivery of prescribed parameters. No adverse events were observed during the in vivo test that confirmed usability and safety together with accuracy of treatment delivery in different modalities. In general, the machine was rated by physicians and nurses involved in the evaluation as practical and easy to use, although a specific training is required to familiarize with the equipment. A large-scale multicenter beta trial is required to confirm the results reported in this preliminary evaluation in terms of safety, accuracy and performance of Kibou\uae

Predicting Acute Kidney Injury in Intensive Care Unit Patients: The Role of Tissue Inhibitor of Metalloproteinases-2 and Insulin-Like Growth Factor-Binding Protein-7 Biomarkers

Background: Acute kidney injury (AKI) diagnosis is based on a rise in serum creatinine and/or fall in urine output. It has been shown that there are patients that fulfill AKI definition but do not have AKI, and there are also patients with evidence of renal injury who do not meet any criteria for AKI. Recently the innovative and emerging proteomic technology has enabled the identification of novel biomarkers that allow improved risk stratification. Methods: Tissue inhibitor of metalloproteinases-2 (TIMP-2), insulin-like growth factor-binding protein 7 (IGFBP7) were measured to a cohort of 719 consecutive patients admitted to Intensive Care Unit (ICU). The primary endpoint was the evaluation of clinical performances of the biomarkers focusing on the probability do develop AKI in the first 7 days. Results: The Kaplan-Meier analysis considering the first 7 days of ICU stay suggested a lower risk of developing AKI (p < 0.0001) for patients with a negative (<0.3; TIMP-2 17IGFBP7) test. Conclusion: (TIMP-2 17IGFBP7) at ICU admission has a good performance in predicting AKI, especially in the first 4 days in ICU. \ua9 2018 S. Karger AG, Basel