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Laser wakefield acceleration (LWFA) may achieve TeV/m gradients using high-density solid-state plasmas as accelerating media. However, the application of bulk solid materials requires attosecond laser pulses, such as X-ray lasers, to drive wakefields at these high densities. Additionally, the short wakefield wavelengths associated with solid-state plasmas greatly limit the accelerating length. An alternative approach employs 2D carbon-based nanomaterials, like graphene or carbon nanotubes (CNTs), configured into structured targets. These nanostructures are designed with voids or low-density regions to effectively reduce the overall plasma density. This reduction enables the use of longer-wavelength lasers and also extends the plasma wavelength and the acceleration length. In this study, we present, to our knowledge, the first numerical demonstration of electron acceleration via self-injection into a wakefield bubble driven by an infrared laser pulse in structured CNT targets, similar to the behavior observed in gaseous plasmas for LWFA in the nonlinear (or bubble) regime. Using the PIConGPU code, bundles of CNTs are modeled in a 3D geometry as 25 nm-thick carbon tubes with an initial density of . The carbon plasma is ionized by a three-cycle, 800 nm wavelength laser pulse with a peak intensity of , achieving an effective plasma density of . The same laser also drives the wakefield bubble, responsible for electron self-injection and acceleration. Simulation results indicate that fs-long electron bunches with hundreds of pC charge can be self-injected and accelerated at gradients exceeding 1 TeV/m. Both charge and accelerating gradient figures are unprecedented when compared with LWFA in gaseous plasma.

Bent crystal are widely used as optics for X-rays, but via the phenomenon of planar channeling they may act as waveguide for relativistic charged particles beam as well, outperforming some of the traditional technologies currently employed. A physical description of the phenomenon and the resulting potential for applications in a particle accelerator is reported. The elastic properties of the anisotropic crystal lattice medium are discussed, introducing different types of curvature which can enable a wide array of bending schemes optimized for each different case features. The technological development of machining strategy and bending solutions useful for the fabrication of crystals suitable in high energy particle manipulations are described. As well as the high precision characterization processes developed in order to satisfy the strict requirements for installation in an accelerator. Finally, the characterization of channeling phenomenon in bent crystal is described, pointing out several experimental setups suitable to comply each specific case constrains.

Background: Immune thrombocytopenia (ITP) and autoimmune hemolytic anemia (AIHA) show good responses to frontline steroids. About two-third of cases relapse and require second-line treatment, including rituximab, mainly effective in AIHA, and thrombopoietin-receptor agonists (TPO-RAs) in ITP, while the use of splenectomy progressively decreased due to concerns for infectious/thrombotic complications. For those failing second line, immunosuppressants may be considered. Objectives: The aim of this study was to evaluate the efficacy of cyclosporine treatment in patients with ITP and AIHA. Design: In this retrospective study, we evaluated the efficacy and safety of cyclosporine A (CyA) in ITP (N = 29) and AIHA (N = 10) patients followed at two reference centers in Milan, Italy. Methods: Responses were classified as partial [Hb > 10 or at least 2 g/dl increase from baseline, platelets (PLT) > 30 × 109/l with at least doubling from baseline] and complete (Hb > 12 g/dl or PLT > 100 × 109/l) and evaluated at 3, 6, and 12 months. Treatment emergent adverse events were also registered. Results: The median time from diagnosis to CyA was 35 months (3–293), and patients had required a median of 4 (1–8) previous therapy lines. Median duration of CyA was 28 (2–140) months and responses were achieved in 86% of ITP and 50% of AIHA subjects. Responders could reduce or discontinue concomitant treatment and resolved PLT fluctuations on TPO-RA. CyA was generally well tolerated, and only two serious infectious complications in elderly patients on concomitant steroids suggesting caution in this patient population. Conclusion: CyA may be advisable in ITP, which is not well controlled under TPO-RA, and in AIHA failing rituximab, particularly if ineligible in clinical trial.

Central nervous system (CNS) lesions, especially invasive fungal diseases (IFDs), in immunocompromised patients pose a great challenge in diagnosis and treatment. We report the case of a 48-year-old man with acute myeloid leukaemia and probable pulmonary aspergillosis, who developed hyposthenia of the left upper limb, after achieving leukaemia remission and while on voriconazole. Magnetic resonance imaging (MRI) showed oedematous CNS lesions with a haemorrhagic component in the right hemisphere with lepto-meningitis. After 2 weeks of antibiotics and amphotericin-B, brain biopsy revealed chronic inflammation with abscess and necrosis, while cultures were negative. Clinical recovery was attained, he was discharged on isavuconazole and allogeneic transplant was postponed, introducing azacitidine as a maintenance therapy. After initial improvement, MRI worsened; brain biopsy was repeated, showing similar histology; and 16S metagenomics sequencing analysis was positive (Veilonella, Pseudomonas). Despite 1 month of meropenem, MRI did not improve. The computer tomography and PET scan excluded extra-cranial infectious–inflammatory sites, and auto-immune genesis (sarcoidosis, histiocytosis, CNS vasculitis) was deemed unlikely due to the histological findings and unilateral lesions. We hypothesised possible IFD with peri-lesion inflammation and methyl-prednisolone was successfully introduced. Steroid tapering is ongoing and isavuconazole discontinuation is planned with close follow-up. In conclusion, the management of CNS complications in immunocompromised patients needs an interdisciplinary approach.

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare hematologic malignancy with aggressive clinical course and poor prognosis. Diagnosis is based on detection of CD4+ CD56+, CD123high, TCL-1+, and blood dendritic cell antigen-2/CD303+ blasts, together with the absence of lineage specific antigens on tumour cells. In this report we present a case of BPDCN presenting with extramedullary and bone marrow involvement, extensively studied by flow cytometry and immunohistochemistry, who achieved complete remission after acute lymphoblastic leukemia like chemotherapy and allogeneic hematopoietic stem cell transplantation.

Electromagnetic processes of charged particles interaction with oriented crystals provide a wide variety of innovative applications such as beam steering, crystal-based extraction/collimation of leptons and hadrons in an accelerator, a fixed-target experiment on magnetic and electric dipole moment measurement, X-ray and gamma radiation source for radiotherapy and nuclear physics and a positron source for lepton and muon colliders, a compact crystalline calorimeter as well as plasma acceleration in the crystal media. One of the main challenges is to develop an up-to-date, universal and fast simulation tool to simulate these applications. We present a new simulation model of electromagnetic processes in oriented crystals implemented into Geant4, which is a toolkit for the simulation of the passage of particles through matter. We validate the model with the experimental data as well as discuss the advantages and perspectives of this model for the applications of the oriented crystals mentioned above.

A particle traversing a crystal aligned with one of its crystallographic axes experiences a strong electromagnetic field that is constant along the direction of motion over macroscopic distances. For and γ -rays with energies above a few GeV , this field is amplified by the Lorentz boost, to the point of exceeding the Schwinger critical field E 0 ∼ 1.32 × 10 16 V / cm . In this regime, nonlinear quantum-electrodynamical effects occur, such as the enhancement of intense electromagnetic radiation emission and pair production, so that the electromagnetic shower development is accelerated and the effective shower length is reduced compared to amorphous materials. We have investigated this phenomenon in lead tungstate ( PbWO 4 ), a high- Z scintillator widely used in particle detection. We have observed a substantial increase in scintillation light at small incidence angles with respect to the main lattice axes. Measurements with 120 GeV electrons and γ -rays between 5 and 100 GeV demonstrate up to a threefold increase in energy deposition in oriented samples. These findings challenge the current models of shower development in crystal scintillators and could guide the development of next-generation accelerator- and space-borne detectors.

Crystals with small thickness along the beam exhibit top performance for steering particle beams through planar channeling. For such crystals, the effect of nuclear dechanneling plays an important role because it affects their efficiency. We addressed the problem through experimental work carried out with 400 GeV/c protons at fixed-target facilities of CERN-SPS. The dependence of efficiency vs. curvature radius has been investigated and compared favourably to the results of modeling. A realistic estimate of the performance of a crystal designed for LHC energy including nuclear dechanneling has been achieved.

Introduction: The first-line therapy for patients with low-risk myelodysplastic syndromes (MDSs) commonly consists of erythropoietin stimulating agents (ESAs), with a response rate ranging from 34 to 62%. For nonresponder patients, outside clinical trials, blood transfusions are the most frequent therapeutic option, with detrimental effect on the quality of life and with risks of iron-overload. Since no studies have been yet conducted on this topic, we investigated the potential predictive role of bone marrow (BM) histological evaluation in patients treated with ESAs. Materials and Methods: We performed a morphological and immunohistochemical retrospective analysis of BM biopsies of 96 patients with low-risk MDSs subsequently treated with ESAs. Results: In our series, substantial morphological overlap was found between responder and nonresponder patients. On the contrary, patients with a percentage of CD34-positive blasts >3% or with p53 protein expression <1% responded with a significantly higher frequency to ESAs. Conclusions: Our study reinforces the role of BM biopsy as diagnostic tool in MDSs, being also able to supply information related to response to ESAs and to its loss over time.

Short-period crystalline undulators have the potential to enable intense and monochromatic sources of hard X andγradiation. Three crystalline undulators were manufactured and their structural properties were characterized at the ESRF x-ray light source. In particular, a crystalline undulator consists in a periodically bent crystal in which channeled electrons or positrons follow the bending of the crystalline planes, thus generating electromagnetic radiation in analogy with standard magnetic undulators. State-of-the-art magnetic undulators can be built with a period of no less than a few cm. On the other hand, a crystalline undulator could be built with a period down to the sub-mm range. Thus, a crystalline undulator would allow generating harder photons. Since the radiator consists of a small crystal, a crystalline undulator is a valid and low-cost alternative for intense hard radiation production at electron accelerator facilities. The three samples were realized at the INFN laboratory of Ferrara, Italy, through the grooving method, namely a method developed to induce a self-standing and adjustable deformation to a crystal. The samples showed a uniform and sinusoidal curvature, thus proving that the grooving method is suitable for building crystalline undulators.