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Experimental cross sections σ lab (E) of the 6 Li(p, α ) 3 He reaction, available in literature, are reanalyzed to evaluate the energy dependence of the bare-nucleus cross section, σ lab (E) , down to energies of astrophysical interest. A new extrapolation below 100 keV is obtained through a theoretical description of laboratory data in a R-matrix calculation that was fitted to published data at higher energies in the range 100 keV ≤ E ≤ 1000 keV . This approach is complementary to the standard one where the extrapolation is performed by fitting the experimental trend with a polynomial astrophysical S factor. Quantities of astrophysical interest, such as the zero-energy S factor and the electron screening potential, are evaluated and compared with literature values. [ABSTRACT FROM AUTHOR]

For the first time in an application to nuclear astrophysics, a process induced by the unstable 5 He = ( 4 He-n) nucleus, the 3 He+ 5 He → 2 α reaction, has been studied through the Trojan Horse Method (THM). For that purpose, the quasi-free (QF) contribution of the 9 Be( 3 He, α α ) 4 He reaction was selected at E 3 He = 4 MeV incident energy. The reaction was studied in a kinematically complete experiment following a recent publication (Spitaleri et al. in Eur Phys J A 56:18, 2020), where for the quasi free contribution the momentum distribution between α and 5 He particle cluster in the 9 Be nucleus in the ground state have been extracted. The angular distribution of the QF 3 He+ 5 He → 2 α reaction was measured at θ cm = 78 ∘ –115 ∘ . The energy dependence of the differential cross section of the 3 He+ 5 He → 2 α virtual reaction was extracted in the energy range E cm = 0–650 keV. The total cross section obtained from the Trojan-horse method was normalized to absolute cross sections from a theoretical calculation in the energy range E cm =300–620 keV. [ABSTRACT FROM AUTHOR]

A new study of the quasi-free contribution to the 3 He + 9 Be → 3 α reaction (Q value = 19.004 MeV) at low E 3 He energy is presented. The reaction was studied in a kinematically complete experiment at beam energy of 4 MeV. To clarify the presence of the quasi-free mechanism, the 4 He – 5 He momentum distribution of the 9 Be ground state was extracted. Standard tests were also carried out to confirm the presence of the quasi-free contribution and are reported in this work. The full width at half maximum of the 4 He – 5 He inter-cluster momentum distribution inside 9 Be was measured with improved accuracy, by adopting several different approaches that all led to consistent results. These preliminary investigations on the reaction mechanism are fundamental for future studies employing the Trojan Horse Method, with the 5 He unbound nucleus as a virtual projectile. [ABSTRACT FROM AUTHOR]

In the framework of the experimental campaign of the ( p , α ) and ( n , α ) reactions cross sections measurement involving the 10, 11B isotopes, different ( n , α ) cross section measurements have been performed at ultra-low energy. In this work, the 10B(n, α )7Li reaction was investigated through the Trojan Horse Method, by means of the Quasi-Free (QF) 2H(10B, α 7 Li)1H reaction at 30 MeV of beam energy. As in the standard THM approach, the measurement has been performed in inverse kinematics using a 10B beam. The excitation function of the 10B(n, α )7Li reaction has been measured at a center-of-mass energy between 0 and 700 keV. The data were compared with the existing experimental ones. Even if the energy resolution of the present experiment did not allow a separation between the channels ( n , α 0 ) and ( n , α 1 ) the low energy cross section and the angular distribution are presented, pointing out once more the ability of the method in studying neutron induced reactions using deuteron as source of virtual neutrons. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this prospective study was to investigate the agreement in findings between ECG-gated CT and transoesophageal echocardiography (TEE) in patients with aortic prosthetic valve endocarditis (PVE).Methods: Twenty-seven consecutive patients with PVE underwent 64-slice ECG-gated CT and TEE and the results were compared. Imaging was compared with surgical findings (surgery was performed in 16 patients).Results: TEE suggested the presence of PVE in all patients [thickened aortic wall (n = 17), vegetation (n = 13), abscess (n = 16), valvular dehiscence (n = 10)]. ECG-gated CT was positive in 25 patients (93 %) [thickened aortic wall (n = 19), vegetation (n = 7), abscess (n = 18), valvular dehiscence (n = 7)]. The strength of agreement [kappa (95 % CI)] between ECG-gated CT and TEE was very good for thickened wall [0.83 (0.62-1.0)], good for abscess [0.68 (0.40-0.97)] and dehiscence [0.75 (0.48-1.0)], and moderate for vegetation [0.55 (0.26-0.88)]. The agreement was good between surgical findings (abscess, vegetation and dehiscence) and imaging for ECG-gated CT [0.66 (0.49-0.87)] and TEE [0.79 (0.62-0.96)] and very good for the combination of ECG-gated CT and TEE [0.88 (0.74-1.0)].Conclusion: Our results indicate that ECG-gated CT has comparable diagnostic performance to TEE and may be a valuable complement in the preoperative evaluation of patients with aortic PVE. [ABSTRACT FROM AUTHOR]

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The erythrocyte skeleton plays an essential role in determining the shape and deformability of the red cell. Disruption of the interaction between components of the red cell membrane skeleton may cause loss of structural and functional integrity of the membrane. Several observations based on studies in vitro strongly suggest that phosphorylation may modify interactions between proteins, leading to a reduced affinity. In particular, increased phosphorylation of beta-spectrin decreases membrane mechanical stability. In order to investigate the presence of membrane protein defects we investigated the erythrocyte membrane protein composition and phosphorylation in 22 children with leukemia at diagnosis and during the remission phase. Sixteen children had acute lymphoblastic leukemia (ALL), three had chronic myeloid leukemia (CML) and three had acute myeloid leukemia (AML). Ten patients (eight ALL and two CML) displayed elliptocytosis and poikilocytosis, an increase of spectrin dimers (41.8 +/- 15.6) and an enhanced phosphorylation of beta-spectrin (108 +/- 15%) at diagnosis. These alterations disappeared during the remission phase. This is the first demonstration of a reversible erythrocyte membrane alteration in leukemia. Since the beta-spectrin phosphate sites are located near the C-terminal region and close to the head of the beta-chain that is involved in dimer-dimer interaction, we supposed that the beta-chain phosphorylation has an effect upon the interactions between spectrin dimers, ie the tetramerization process. The weakening of this process should be responsible for the presence of elliptocytes and poikilocytes as reported in hereditary elliptocytosis and pyropoikilocytosis. [ABSTRACT FROM AUTHOR]

α Hereditary elliptocytosis (HE) is due to the duplication of TTG codon 154 (leucine) of α-spectrin and is associated with a constant haplotype. It was encountered exclusively in African and American Blacks, and in North Africans. We assumed that it diffused from the Benin-Togo area to Northern Africa. We now report two South Italian families with α HE. The phenotype fully conformed to previous descriptions. The mode of transmission was dominant; however, the manifestations were more pronounced when the common, low expression level α allele occurred in trans to the α allele, also conforming to previous records. The mutation underlying α HE turned out to be, again, the duplication of TTG codon 154 and the associated haplotype was the same as that encountered previously (+-+; XbaI, PvuII, MspI). Thus, the α allele found in Italy must have been introduced from North Africa across the Sicilian channel and would ultimately have originated from the Benin-Togo area. It would witness the same migratory stream as that followed by the Benin type haemoglobin S allele, which is also present in Southern Italy. [ABSTRACT FROM AUTHOR]

We present here our experience of patent foramen ovale closure through a mini-invasive surgical technique. With the new surgical platform termed Heartport System, it is possible to install extra-corporeal circulation and to obtain cardioplegic arrest of the heart with endovascular techniques. This allows the operation of closure to be entirely performed through a micro-thoracotomy (Port-access surgery) in the right 4th intercostal space. Sixty-one patients underwent this surgical correction and seventeen of them (26%) had a diagnosis of patent foramen ovale, 12 with an history of cerebrovascular accidents. They are all alive and well after a mean follow-up of 16 months, with no recurrence of the inter-atrial communication and free from new neurological events. The post-operative course was uneventful with patients discharged on postoperative day 4. This technique shows a 100% efficacy, minimise surgical trauma, allows a quick recovery and offers excellent cosmetic results with no scarring. We believe that this procedure must be regarded as the “golden standard” for the closure of atrial septal defects. [ABSTRACT FROM AUTHOR]

After myocardial infarction (MI), emergency hematopoiesis produces inflammatory myeloid cells that accelerate atherosclerosis and promote heart failure. Since the balance between glycolysis and mitochondrial metabolism regulates hematopoietic stem cell homeostasis, metabolic cues may influence emergency myelopoiesis. Here, we show in humans and female mice that hematopoietic progenitor cells increase fatty acid metabolism after MI. Blockade of fatty acid oxidation by deleting carnitine palmitoyltransferase ( Cpt1A ) in hematopoietic cells of Vav1 Cre/+ Cpt1A fl/fl mice limited hematopoietic progenitor proliferation and myeloid cell expansion after MI. We also observed reduced bone marrow adiposity in humans, pigs and mice following MI. Inhibiting lipolysis in adipocytes using Adipoq CreERT2 Atgl fl/fl mice or local depletion of bone marrow adipocytes in Adipoq CreERT 2iDTR mice also curbed emergency hematopoiesis. Furthermore, systemic and regional sympathectomy prevented bone marrow adipocyte shrinkage after MI. These data establish a critical role for fatty acid metabolism in post-MI emergency hematopoiesis., Competing Interests: Competing interests statement All other authors declare no conflicts of interest, financial or otherwise.