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The PTOLEMY transverse drift filter is a new concept to enable precision analysis of the energy spectrum of electrons near the tritium beta-decay endpoint. This paper details the implementation and optimization methods for successful operation of the filter. We present the first demonstrator that produces the required magnetic field properties with an iron return-flux magnet. Two methods for the setting of filter electrode voltages are detailed. The challenges of low-energy electron transport in cases of low field are discussed, such as the growth of the cyclotron radius with decreasing magnetic field, which puts a ceiling on filter performance relative to fixed filter dimensions. Additionally, low pitch angle trajectories are dominated by motion parallel to the magnetic field lines and introduce non-adiabatic conditions and curvature drift. To minimize these effects and maximize electron acceptance into the filter, we present a three-potential-well design to simultaneously drain the parallel and transverse kinetic energies throughout the length of the filter. These optimizations are shown, in simulation, to achieve low-energy electron transport from a 1 T iron core (or 3 T superconducting) starting field with initial kinetic energy of 18.6 keV drained to, 29 pages, 25 figures

Different types of tissues respond differently to the action of oxidative stress. The visual system is very sensitive to oxidative action due to continuous exposure to light. In consideration of the growing interest of scientific studies towards various compounds endowed with antioxidant and anti-inflammatory properties, we performed a review of the literature focusing on the use of some antioxidant molecules for the treatment of conditions affecting the visual system. In this study, we focused on the ability of two antioxidant agents, the small molecule ��-lipoic acid (ALA) and the enzyme superoxide dismutase (SOD), to influence the neurodegenerative physiological processes related to aging and oxidative stress affecting the ocular segment. The literature data report that ALA and SOD can protect against neurodegenerative effects both the optic nerve and retina and, if administered together, they are able to lower the levels of oxidative stress, thus preventing neurodegeneration and reducing the apoptotic process., EXCLI Journal; 21:Doc544; ISSN 1611-2156

The SARS-Cov-2 pandemic significantly impacted on oncology practice across the globe. There is uncertainty as to the contribution of patients' demographics and oncological features on severity and mortality from Covid-19 and little guidance as to the role of anti-cancer and anti-Covid-19 therapy in this population. In a multi-center study of 890 cancer patients with confirmed Covid-19 we demonstrated a worsening gradient of mortality from breast cancer to haematological malignancies and showed that male gender, older age, and number of co-morbidities identifies a subset of patients with significantly worse mortality rates from Covid-19. Provision of chemotherapy, targeted therapy and immunotherapy did not worsen mortality. Exposure to antimalarials was associated with improved mortality rates independent of baseline prognostic factors. This study highlights the clinical utility of demographic factors for individualized risk-stratification of patients and support further research into emerging anti-Covid-19 therapeutics in SARS-Cov-2 infected cancer patients.

Metal monochalcogenides (MX) have recently been rediscovered as two-dimensional materials with electronic properties highly dependent on the number of layers. Although some intriguing properties appear in the few-layer regime, the carrier mobility of MX compounds increases with the number of layers, motivating the interest in multilayered heterostructures or bulk materials. By means of angle-resolved photoemission spectroscopy (ARPES) measurements and density functional theory calculations, we compare the electronic band structure of bulk ε−GaSe and ε-InSe semiconductors. We focus our attention on the top valence band of the two compounds along main symmetry directions, discussing the effect of spin-orbit coupling and contributions from post-transition-metal (Ga or In) and Se atoms. Our results show that the top valence band at Γ point is dominated by Se pz states, while the main effect of Ga or In appears more deeply in binding energy, at the Brillouin zone corners, and in the conduction band. These findings explain also the experimental observation of a hole effective mass rather insensitive to the post-transition metal. Finally, by means of spin-resolved ARPES and surface band structure calculations we describe Rashba-Bychkov spin splitting of surface states in ε−InSe., The support by the Fundamental Research Program of the State Academies of Sciences (line of research III.23.2.9), and the project EUROFEL-ROADMAP ESFRI, are gratefully acknowledged. This work has been partly performed in the framework of the Nanoscience Foundry and Fine Analysis (NFFA—MIUR Italy Progetti Internazionali) facility. M. Castriota and F. Ciuchi are acknowledged for having performed, respectively, Raman and XRD characterization of GaSe and InSe samples. This work was supported by Saint Petersburg State University (Grant No. ID 51126254).

LaBr3:Ce has been showing very promising characteristics as gamma ray imager and spectrometer. In particular its excellent energy resolution values (6% at 140 keV and not, vert, similar3% FWHM at 662 keV), obtained when coupled to a PMT, make it the major competitor of semiconductor detectors working at room temperature. In order to improve its imaging performances, the LaBr3:Ce can easily work as continuous detector allowing sub-millimeter spatial resolution values at 140 keV photon energy when coupled to a Position Sensitive PMT. Further interesting characteristics like a short scintillation decay time (16 ns), a very high light yield (63 000 photons/MeV) and a low afterglow are attracting the scientific community for the potential improvement of a wide range of applications in medicine like PET, SPECT and CT instrumentation. In this paper, we present some preliminary imaging results obtained by coupling H8500 Hamamatsu Flat Panel PMT to two LaBr3:Ce crystals with 50×50 mm2 area, 5 and 10 mm thickness respectively. With the aim to propose a single detector able to combine functional information, for example from Single Photon Emission technique, with the morphological ones from X-ray imaging the spatial resolution results obtained in the energy range between 30 and 302 keV are analyzed and discussed. We obtained very interesting spatial resolution results for gamma ray energy value greater than 60 keV (better than 1 mm, intrinsic value), while in the energy range proper to X-ray applications, like RX-Mammography (about 30 keV), the spatial resolution values resulted about 2 mm.

Hypothyroidism and gestational diabetes are common endocrine disorders in pregnancy. Our aim is to evaluate the outcome of newborns from mothers with hypothyroidism and from mothers with gestational diabetes.The study analysed 216 newborns: 112 from mothers with gestational diabetes and 104 from mothers with hypothyroidism. For each case, we included as a control a newborn of same sex and gestational age from a mother without diabetes or thyreopathy.In newborns from mothers with gestational diabetes there was an increased frequency of hypoglycaemia and hypocalcaemia, of lower head circumference and of small-for-gestational age (SGA) birth or macrosomy (LGA) than controls. The newborns from mothers with hypothyroidism are more frequently SGA or LGA and they have a slightly increased risk of hypoglycaemia.Newborns from mothers with diabetes mellitus or hypothyroidism have an increased risk of being SGA or LGA, and to develop a mild transient hypoglycaemia. Newborns from mothers with diabetes mellitus have also an increased risk to develop hypocalcaemia and to have a lower head circumference than controls. Thus, to prevent SGA or LGA births, it is very important an early diagnosis and treatment, and a strict metabolic control of these conditions.

Although scintimammography is routinely used in the hospitals it had not the expected large diffusion. The low specificity of SESTAMIBI /sup 99m/Tc and the geometrical restrictions of prone scintimammography further contributed in limiting the clinical sensitivity for sub centimeter lesions. Researchers aware that to overcome intrinsic limitation of radio-pharmaceutical, they are optimized compact imager able to detect small amount of radioactivity emitted from 5 mm or less tumors. To investigate the overall imaging characteristics of scintillation imagers for scintimammography, a number of small gamma camera prototypes were assembled, based on PSPMT of first and last generation. They were coupled to a number of NaI(Tl) and CsI(Tl) scintillation both planar and pixellated, with different pixel size. Measurements were performed by line and circular source as well as by 3 mm to 10 mm diameter tumor phantoms. Spatial resolution seems the dominant factor, in detection of 5 mm and 3 mm tumor size. The best results were obtained from the scintillation crystals arrays coupled to Hamamatsu flat panel PMT. Decreasing crystal pixel size, contrast mean values slightly changed but their accuracy increases, demonstrating the influence of digitization on image quality. MTF curve obtained by planar NaI(Tl) integral assembly shows an improvement with a response at the highest frequency equal to one obtained from collimator parallel hole Monte Carlo simulation.

Nitrogen retrieval and assimilation by ectomycorrhizal fungi is thought to play a central role in the economy of the symbiotic interaction. Here, we report on the molecular characterization of the key N assimilation enzyme glutamine synthetase from the mycorrhizal ascomycete Tuber borchii (TbGS). TbGS displayed a strong positive co-operativity (n=1.7+/-0.29) and an unusually high S0,5 value (54+/-16mM; S0,5 is the substrate concentration value at which v=1/2 Vmax) for glutamate, and a correspondingly low sensitivity towards inhibition by the glutamate analogue herbicide phosphinothricin. T h e T b G S m R N A, which is encoded by a single-copy gene in the Tuber genome, was upregulated in N starved mycelia and returned to basal levels upon resupplementation of various forms of N, the most effective of which was nitrate. Both responses were accompanied by parallel variations of TbGS protein amount and glutamine synthetase activity, indicating that TbGS levels are primarily controlled at the pretranslational level. As revealed by a comparative analysis of TbGS and of the mRNAs for the metabolically related enzymes glutamate dehydrogenase and glutamate synthase, TbGS is not only the sole messenger that positively responds to N starvation, but also the most abundant under N limiting conditions. A similar, but even more discriminating expression pattern, with practically undetectable GDH mRNA levels, was observed in fruitbodies. The TbGS mRNA was also found to be expressed in symbiosis-engaged hyphae, with higher hybridation signals in hyphae that were penetrating among and within root cells.

The work describes the scintillating performances of a new class of scintillators: LaCl3:Ce and LaBl3:Ce, producing a photon number higher than NaI(Tl) at a wavelength suited for photocatodes.The crystals were tested with flat panel Position Sensitive Photomultiplier (PSPMT).

Proprietà tecnologiche della carne di coniglio arricchita in PUFA n-3 – La ricerca ha avuto lo scopo di valutare alcune caratteristiche tecnologiche di prodotti trasformati (impasti di carne macinata e hamburger) provenienti da conigli alimentati con diete prive o contenenti l’8% di semi di lino. L’inclusione di semi di lino nella dieta ha determinato un significativo aumento della suscettibilità ossidativa (TBARS) degli impasti sia a 3 che a 6 mesi di conservazione a -20°C, mentre l’analisi sensoriale ha fatto rilevare la comparsa di sapore di rancido solo dopo 3 mesi di conservazione. Le variazioni di colore degli hamburger durante la conservazione a 2-4°C in atmosfera ordinaria o sottovuoto sono risultate comparabili nei due gruppi sperimentali.

Metal monochalcogenides (MX) have recently been rediscovered as two-dimensional materials with electronic properties highly dependent on the number of layers. Although some intriguing properties appear in the few-layer regime, the carrier mobility of MX compounds increases with the number of layers, motivating the interest in multilayered heterostructures or bulk materials. By means of angle-resolved photoemission spectroscopy (ARPES) measurements and density functional theory calculations, we compare the electronic band structure of bulk epsilon-GaSe and epsilon-InSe semiconductors. We focus our attention on the top valence band of the two compounds along main symmetry directions, discussing the effect of spin-orbit coupling and contributions from post-transition-metal (Ga or In) and Se atoms. Our results show that the top valence band at Gamma point is dominated by Se p(z) states, while the main effect of Ga or In appears more deeply in binding energy, at the Brillouin zone corners, and in the conduction band. These findings explain also the experimental observation of a hole effective mass rather insensitive to the post-transition metal. Finally, by means of spin-resolved ARPES and surface band structure calculations we describe Rashba-Bychkov spin splitting of surface states in epsilon-InSe.