36 research outputs found

    A Mathematical Model of Flavescence Dor\'ee Epidemiology

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    Flavescence dor\'ee (FD) is a disease of grapevine transmitted by an insect vector, ScaphoideusScaphoideus titanustitanus Ball. At present, no prophylaxis exists, so mandatory control procedures (e.g. removal of infected plants, and insecticidal sprays to avoid transmission) are in place in Italy and other European countries. We propose a model of the epidemiology of FD by taking into account the different aspects involved into the transmission process (acquisition of the disease, latency and expression of symptoms, recovery rate, removal and replacement of infected plants, insecticidal treatments, and the effect of hotbeds). The model was constructed as a system of first order nonlinear ODEs in four compartment variables. We perform a bifurcation analysis of the equilibria of the model using the severity of the hotbeds as the control parameter. Depending on the non-dimensional grapevine density of the vineyard we find either a single family of equilibria in which the health of the vineyard gradually deteriorates for progressively more severe hotbeds, or multiple equilibria that give rise to sudden transitions from a nearly healthy vineyard to a severely deteriorated one when the severity of the hotbeds crosses a critical value. These results suggest some lines of intervention for limiting the spread of the disease

    Dynamics of (4+1)-Dihedrally Symmetric Nearly Parallel Vortex Filaments

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    We give a detailed analytical and numerical description of the global dynamics of 4+1 points interacting through the singular logarithmic potential and subject to the following symmetry constraint: at each instant 4 of them form an orbit of the Klein group D 2 of order 4. The main device in order to achieve our results is to use a McGehee-like transformation introduced in (Paparella and Portaluri in Global dynamics of the dihedral singular logarithmic potential and nearly parallel vortex filaments, 2011) for a problem analogous to the present one. After performing this transformation in order to regularize the total collision, we study the rest-points of the flow, the invariant (stable and unstable) manifolds and we derive some interesting information about the global dynamics

    Biological control of the chestnut gall wasp with \emph{T. sinensis}: a mathematical model

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    The Asian chestnut gall wasp \emph{Dryocosmus kuriphilus}, native of China, has become a pest when it appeared in Japan, Korea, and the United States. In Europe it was first found in Italy, in 2002. In 1982 the host-specific parasitoid \emph{Torymus sinensis} was introduced in Japan, in an attempt to achieve a biological control of the pest. After an apparent initial success, the two species seem to have locked in predator-prey cycles of decadal length. We have developed a spatially explicit mathematical model that describes the seasonal time evolution of the adult insect populations, and the competition for finding egg deposition sites. In a spatially homogeneous situation the model reduces to an iterated map for the egg density of the two species. While the map would suggest, for realistic parameters, that both species should become locally extinct (somewhat corroborating the hypothesis of biological control), the full model, for the same parameters, shows that the introduction of \emph{T. sinensis} sparks a traveling wave of the parasitoid population that destroys the pest on its passage. Depending on the value of the diffusion coefficients of the two species, the pest can later be able to re-colonize the empty area left behind the wave. When this occurs the two populations do not seem to attain a state of spatial homogeneity, but produce an ever-changing pattern of traveling waves

    Surgical Brain Metastases: Management and Outcome Related to Prognostic Indexes: A Critical Review of a Ten-Year Series

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    Brain metastasis are the most common neoplastic lesions of the nervous system. Many cancer patients are diagnosed on the basis of a first clinical presentation of cancer on the basis of a single or multiple brain lesions. Brain metastases are manifestations of primary disease progression and often determine a poor prognosis. Not all patients with a brain metastases undergo surgery: many are submitted to alternative or palliative treatments. Management of patients with brain metastases is still controversial, and many studies have been developed to determine which is the best therapy. Furthermore, management of patients operated for a brain metastasis is often difficult. Chemotherapy, stereotactic radiosurgery, panencephalic radiation therapy, and surgery, in combination or alone, are the means most commonly used. We report our experience in the management of a ten-year series of surgical brain metastasis and discuss our results in the preoperative and postoperative management of this complex condition

    Safety culture to improve accidental events reporting in radiotherapy

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    The potential for unintended and adverse radiation exposure in radiotherapy is real and should be studied because radiotherapy is a highly complex, multistep process which requires input from numerous individuals from different areas and steps of the radiotherapy workflow. The 'Incident' (I) is a consequence of which are not negligible from the point of view of protection or safety. A 'near miss' (NM) is defined as an event which is highly likely to happen but did not occur. The purpose of this work is to show that through a systematic reporting and analysis of these adverse events, their occurrence can be reduced

    PROMUOVERE LA COMUNICAZIONE SANITARIA IN UN’OTTICA IAP- CENTRED

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    The steady promotion of participatory healthcare, from Empowerment policies for cancer patients to Patient-Reported Outcomes (PROs), is acknowledging the patient- citizen’s status as an Individual Active Participant (IAP), thus establishing a new patient-centred era based on the healing power of words. Given the impact of health communication notably in oncology units, this Participatory Action Research project detected and gave expression to both clinical and social needs in favour of female IAPs treated with radiotherapy. The project consisted of group discussions and support initiatives aimed at: (1) spurring self-awareness; (2) fostering health communication; (3) building a community of female IAPs regionwide.La progressiva promozione di prassi sanitarie partecipative, dal Patto per l’Empowerment del paziente oncologico alla diffusione dei Patient-Reported Outcomes, sta riconoscendo al/la paziente-cittadino/a il suo status di Individuo Attivo e Partecipe (IAP), e sancendo l’ingresso della comunità medica e scientifica in una nuova fase patient- centred: quella delle “parole che curano”. Dato l’impatto della comunicazione sanitaria nei reparti oncologici, il presente progetto di Ricerca-Azione Partecipata ha posto al servizio di donne-IAP trattate con radioterapia l’analisi dei loro bisogni clinici e sociali attraverso gruppi di supporto e discussione tesi a: (1) incentivare autoconsapevolezza; (2) promuovere la comunicazione sanitaria; (3) istituire una comunità di donne-IAP nel territorio pugliese

    Further Clarification of Pain Management Complexity in Radiotherapy: Insights from Modern Statistical Approaches

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    Background: The primary objective of this study was to assess the adequacy of analgesic care in radiotherapy (RT) patients, with a secondary objective to identify predictive variables associated with pain management adequacy using a modern statistical approach, integrating the Least Absolute Shrinkage and Selection Operator (LASSO) algorithm and the Classification and Regression Tree (CART) analysis. Methods: This observational, multicenter cohort study involved 1387 patients reporting pain or taking analgesic drugs from 13 RT departments in Italy. The Pain Management Index (PMI) served as the measure for pain control adequacy, with a PMI score < 0 indicating suboptimal management. Patient demographics, clinical status, and treatment-related factors were examined to discern the predictors of pain management adequacy. Results: Among the analyzed cohort, 46.1% reported inadequately managed pain. Non-cancer pain origin, breast cancer diagnosis, higher ECOG Performance Status scores, younger patient age, early assessment phase, and curative treatment intent emerged as significant determinants of negative PMI from the LASSO analysis. Notably, pain management was observed to improve as RT progressed, with a greater discrepancy between cancer (33.2% with PMI < 0) and non-cancer pain (73.1% with PMI < 0). Breast cancer patients under 70 years of age with non-cancer pain had the highest rate of negative PMI at 86.5%, highlighting a potential deficiency in managing benign pain in younger patients. Conclusions: The study underscores the dynamic nature of pain management during RT, suggesting improvements over the treatment course yet revealing specific challenges in non-cancer pain management, particularly among younger breast cancer patients. The use of advanced statistical techniques for analysis stresses the importance of a multifaceted approach to pain management, one that incorporates both cancer and non-cancer pain considerations to ensure a holistic and improved quality of oncological care

    Ultrasound B-lines for detection of late lung fibrosis in breast cancer patients after radiation therapy

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    Background and purpose. Radiation therapy (RT) for breast cancer after conservative surgery can be life-saving but remains associated with significant late side effects, including lung fibrosis, detected by chest CT. Aim of this study was to assess whether lung ultrasound (LUS) may detect late lung fibrosis through the biomarker of B-lines. Materials and methods. We evaluated 30 women (median age 67 years, range 46-80 years) about 3-8 years after RT (follow up 38-101 months, median 58 months) for left (n = 12) or right (n = 18) breast cancer (stage 1, n = 24; stage 2, n = 6), treated with total dose 40.5 – 50.00 Gy with/without boost dose). In all, both treated and contralateral hemithorax were evaluated. LUS was performed and B-lines evaluated with a 28-region antero-lateral scan, from second to fifth intercostal spaces, along the mid-axillary, anterior axillary, mid-clavicular, and arasternal lines. In each space, the B-lines were counted from 0 = black lung to 10 = white lung. The sum of B-lines in all spaces generated the B-line score of each hemithorax. Results. Median B-line score was higher in the irradiated site than in the contralateral control hemithorax (9, 1st-3rd quartiles: 2-23 vs 3, 1st-3rd quartiles: 1-4; P median value of 2.7 Gy) were associated with more B-lines when compared to lower doses (< 2.7 Gy): 9 vs 5, p < 0.001. Conclusion. RT in female breast cancer survivors is associated with increase in B-lines in the targeted hemithorax, likely due to lung fibrosis, and related to the lung mean dose. LUS can provide a simple “echo-marker” of lung fibrosis.
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