"Magneto-elastic" waves in an anisotropic magnetised plasma

The linear waves that propagate in a two fluid magnetised plasma allowing for a non-gyrotropic perturbed ion pressure tensor are investigated. For perpendicular propagation and perturbed fluid velocity a low frequency (magnetosonic) and a high frequency (ion Bernstein) branch are identified and discussed. For both branches a comparison is made with the results of a truncated Vlasov treatment. For the low frequency branch we show that a consistent expansion procedure allows us to recover the correct expression of the Finite Larmor Radius corrections to the magnetosonic dispersion relation.Comment: 16 pages, 9 figure

Analysis of the effect of different coatings on ejection forces in micro injection moulding

The purpose of this study was to investigate the effects of different mould coatings on ejection force in micro injection moulding, for a selection of thermoplastic polymers. Two semi-crystalline and two amorphous polymers were sorted. According to their potential affinity with the selected injected polymers, three different coatings were chosen: two types of DLC and a CrTiNbN coatingope

Coupling between whistler waves and slow-mode solitary waves

The interplay between electron-scale and ion-scale phenomena is of general interest for both laboratory and space plasma physics. In this paper we investigate the linear coupling between whistler waves and slow magnetosonic solitons through two-fluid numerical simulations. Whistler waves can be trapped in the presence of inhomogeneous external fields such as a density hump or hole where they can propagate for times much longer than their characteristic time scale, as shown by laboratory experiments and space measurements. Space measurements have detected whistler waves also in correspondence to magnetic holes, i.e., to density humps with magnetic field minima extending on ion-scales. This raises the interesting question of how ion-scale structures can couple to whistler waves. Slow magnetosonic solitons share some of the main features of a magnetic hole. Using the ducting properties of an inhomogeneous plasma as a guide, we present a numerical study of whistler waves that are trapped and transported inside propagating slow magnetosonic solitons.Comment: Submitted to Phys. of Plasma

Prophylaxis and therapy of viral infections in pediatric patients treated for malignancy

Infections are still an important cause of mortality and morbidity in pediatric cancer patients. Most of the febrile episodes in immunocompromised patients are classified as a fever of unknown origin (FUO) while bacteria are the more frequent causes of documented infections. Viral infections are also feared during chemotherapy but less data are available on their incidence and morbidity. We reviewed the literature on incidence, morbidity, and mortality of viral infections in children undergoing chemotherapy and discussed the evidence concerning the prophylaxis and the therapy

Imaging-based representation and stratification of intra-tumor heterogeneity via tree-edit distance

Personalized medicine is the future of medical practice. In oncology, tumor heterogeneity assessment represents a pivotal step for effective treatment planning and prognosis prediction. Despite new procedures for DNA sequencing and analysis, non-invasive methods for tumor characterization are needed to impact on daily routine. On purpose, imaging texture analysis is rapidly scaling, holding the promise to surrogate histopathological assessment of tumor lesions. In this work, we propose a tree-based representation strategy for describing intra-tumor heterogeneity of patients affected by metastatic cancer. We leverage radiomics information extracted from PET/CT imaging and we provide an exhaustive and easily readable summary of the disease spreading. We exploit this novel patient representation to perform cancer subtyping according to hierarchical clustering technique. To this purpose, a new heterogeneity-based distance between trees is defined and applied to a case study of prostate cancer. Clusters interpretation is explored in terms of concordance with severity status, tumor burden and biological characteristics. Results are promising, as the proposed method outperforms current literature approaches. Ultimately, the proposed method draws a general analysis framework that would allow to extract knowledge from daily acquired imaging data of patients and provide insights for effective treatment planning

Severe ocular involvement in a newborn with Langerhans Cell Histiocytosis

Abstract Langerhans Cell Histiocytosis (LCH) is a rare proliferative disease of the mononuclear phagocyte system, characterised by tissue infiltration of CD1a + CD207+ histiocytes. The clinical presentation is variable, ranging from unifocal asymptomatic bone involvement to life-threatening multisystem disease, requiring aggressive therapeutic approaches. Intraocular involvement is uncommon and associated to poor visual and general prognosis. We report a case of LCH in a newborn with severe ocular and multisystem risk-organ involvement, unresponsive to several lines of chemotherapy. Off-label administration of vemurafenib led to dramatic improvement at systemic level; however, chronic sequelae of ocular involvement resulted in poor visual prognosis. Intraocular LCH involvement may be asymptomatic and clinical signs delayed, leading to severe complications, especially in newborns and young children. Screening for ocular involvement is essential for early treatment initiation, which can possibly improve the visual outcome. Vemurafenib is effective on systemic involvement, and its role in ocular LCH needs to be evaluated

Current evidence of antifungal prophylaxis and therapy in pediatric patients

Invasive fungal infections (IFI) are an important complication in pediatric haematological and oncological patients who undergo intensive chemotherapy for leukemia, solid tumour at advanced stage or relapsed, and hematopoietic stem cell transplantation. The incidence of IFI is lower than bacterial infection but mortality rate remains high. This review is designed to help paediatric oncologists in choosing the appropriate anti-fungal strategy and agents for prophylaxis, empirical, pre-emptive and specific therapy on the basis of published evidence

Combination antifungal therapy and surgery for the treatment of invasive pulmonary aspergillosis after hematopoietic stem cell transplantation

An 8-year old boy, affected by severe aplastic anemia, developed a probable pulmonary invasive aspergillosis (IA) early after a second unrelated allogeneic hematopoietic stem cell transplant (HSCT). He was treated promptly with the combination of liposomal amphotericin B and caspofungin. Despite the initial stabilization, the patient deteriorated and the antifungal therapy was switched to voriconazole and caspofungin. The patient gradually improved and was discharged home on day +29 post-HSCT on oral voriconazole. On day +119, a sudden episode of hemoptysis occurred and a right superior lobectomy was decided to remove the residual aspergilloma. The patient is now alive and well more than 24 months from HSCT. This case demonstrated that antifungal combination therapy and surgery are valid options to cure pulmonary IA even in patients at high-risk and severely immunosuppressed

Improvement of Legionnaires' disease diagnosis using real-time PCR assay: a retrospective analysis, Italy, 2010 to 2015

AimTo evaluate real-time PCR as a diagnostic method for Legionnaires' disease (LD). Detection of Legionella DNA is among the laboratory criteria of a probable LD case, according to the European Centre for Disease Prevention and Control, although the utility and advantages, as compared to culture, are widely recognised.MethodsTwo independent laboratories, one using an in-house and the other a commercial real-time PCR assay, analysed 354 respiratory samples from 311 patients hospitalised with pneumonia between 2010-15. The real-time PCR reliability was compared with that of culture and urinary antigen tests (UAT). Concordance, specificity, sensitivity and positive and negative predictive values (PPV and NPV, respectively) were calculated.ResultsOverall PCR detected eight additional LD cases, six of which were due to Legionella pneumophila (Lp) non-serogroup 1. The two real-time PCR assays were concordant in 99.4% of the samples. Considering in-house real-time PCR as the reference method, specificity of culture and UAT was 100% and 97.9% (95% CI: 96.2-99.6), while the sensitivity was 63.6% (95%CI: 58.6-68.6) and 77.8% (95% CI: 72.9-82.7). PPV and NPV for culture were 100% and 93.7% (95% CI: 91.2-96.3). PPV and NPV for UAT were 87.5% (95% CI: 83.6-91.4) and 95.8% (95% CI: 93.5-98.2).ConclusionRegardless of the real-time PCR assay used, it was possible to diagnose LD cases with higher sensitivity than using culture or UAT. These data encourage the adoption of PCR as routine laboratory testing to diagnose LD and such methods should be eligible to define a confirmed LD case

The Use of Splenectomy to Manage Platelet Transfusion Refractoriness due to Anti-Human Leukocyte Antibodies in Allogeneic Stem Cell Transplantation

In patients undergoing hematopoietic stem cell transplantation (HSCT), refractoriness to platelet transfusion has been associated with graft failure, delayed engraftment, early mortality and decreased overall survival. Therapeutic strategies include plasma exchange, immunoglobulins, rituximab, and splenectomy. We describe here three patients with refractoriness to platelet transfusion due to anti-human leukocyte antibodies who were splenectomized before HSCT (two cases) and after HSCT (one case) due to the lack of efficacy of other therapies. Splenectomy was uneventful. All three patients achieved a full donor engraftment. We suggest that splenectomy is feasible and effective in HSCT patients to reduce the risk of graft failure or delayed engraftment