13,511 research outputs found
Carbon nanotubes as target for directional detection of light WIMP
In this paper I will briefly introduce the idea of using Carbon Nanotubes
(CNT) as target for the detection of low mass WIMPs with the additional
information of directionality. I will also present the experimental efforts of
developing a Time Projection Chamber with a CNT target inside and the results
of a test beam at the Beam Test Facility of INFN-LNF.Comment: 3 figures, IFAE2017 poster session proceeding
Effect of pretreatment with immune serum on murine sarcoma virus (Moloney) tumour induction and growth.
Regressor serum from MSV-M-infected mice markedly reduced MSV-M oncogenesis when administered i.p. (0-1 ml/mouse) as much as 30 days before i.m. MSV-M infection in adult BALB/c mice. The regressor serum activity appeared to be directly dependent on the amount of IgG, as shown by: (1) inactivity of sera which have low virus-neutralizing antibody content; (2) high effectiveness only of the IgG serum fraction; (3) inactivity of regressor serum incubated with anti-mouse gamma-globulin serum. The regressor serum activity was specific and could not be ascribed to interferon or interferon-inducing factors, antigen-antibody complexes or free antigen. The activity was not suppressed by sublethal irradiation (380 rad) of recipient mice. These results suggest that the activity of regressor serum administered before MSV-M infection is mediated through sensitization of host cells which are not radiosensitive
Migraine and cluster headache show impaired neurosteroids patterns
Background: Perturbation of neuronal excitability contributes to migraine. Neurosteroids modulate the activity of γ-aminobutyric acid A and N-methyl-d-aspartate receptors, and might be involved in the pathogenesis of migraine. Here, we measured plasma levels of four neurosteroids, i.e., allopregnanolone, epiallopregnanolone, dehydroepiandrosterone and deydroepiandrosterone sulfate, in patients affected by episodic migraine, chronic migraine, or cluster headache. Methods: Nineteen female patients affected by episodic migraine, 51 female patients affected by chronic migraine, and 18 male patients affected by cluster headache were recruited to the study. Sex- and age-matched healthy control subjects (31 females and 16 males) were also recruited. Patients were clinically characterized by using validated questionnaires. Plasma neurosteroid levels were measured by liquid chromatography-tandem mass spectrometry. Results: We found disease-specific changes in neurosteroid levels in our study groups. For example, allopregnanolone levels were significantly increased in episodic migraine and chronic migraine patients than in control subjects, whereas they were reduced in patients affected by cluster headache. Dehydroepiandrosterone and dehydroepiandrosterone sulfate levels were reduced in patients affected by chronic migraine, but did not change in patients affected by cluster headache. Conclusion: We have shown for the first time that large and disease-specific changes in circulating neurosteroid levels are associated with chronic headache disorders, raising the interesting possibility that fluctuations of neurosteroids at their site of action might shape the natural course of migraine and cluster headache. Whether the observed changes in neurosteroids are genetically determined or rather result from exposure to environmental or intrinsic stressors is unknown. This might also be matter for further investigation because stress is a known triggering factor for headache attacks in both migraineurs and cluster headache patients
A literature review of hypertensive retinopathy: systemic correlations and new technologies
OBJECTIVE: Hypertensive retinopathy (HR) is the most common ocular manifestation of systemic arterial hypertension. This paper aims to summarize the current knowledge of HR, reviewing its classical features, such as epidemiology, pathophysiology, clinical manifestations, classifications, management and the most significant systemic correlations. We also provide an update on the latest advances in new technologies focusing on novel instrumental classifications. MATERIALS AND METHODS: A literature search was performed to identify articles regarding HR listed in Embase, PubMed, Medline (Ovid) and Scopus database up to 1 December 2021. The reference lists of the analyzed articles were also considered a source of literature information. The following keywords were used in various combinations: hypertensive retinopathy, hypertension and eye, hypertensive retinopathy and systemic correlations, optical coherence tomography (OCT) and hypertensive retinopathy, optical coherence tomography angiography (OCTA) and hypertensive retinopathy, adaptive optics (AO) and hypertensive retinopathy. The authors analyzed all English articles found using the aforementioned Keywords. All the publications were thoroughly reviewed to create a detailed overview of this issue. RESULTS: HR signs have a significative association with cardiovascular, cerebrovascular and other systemic diseases. Patients with arteriosclerotic changes and, at the same time, severe HR, are at increased risk for coronary disease, peripheral vascular disease, stroke and dementia. HR is even now diagnosed and classified by its clinical appearance on a fundoscopic exam that is limited by interobserver variability. New technologies, like OCT, OCTA, AO and artificial intelligence may be used to develop a new instrumental classification that could become an objective and quantitative method for the evaluation of this disease. They could be useful to evaluate the subclinical retinal microvascular changes due to hypertension that may reflect the involvement of other vital organs. CONCLUSIONS: The eye is the only organ in the human body where changes in the blood vessels due to systemic hypertension can be studied in vivo. All doctors should be familiar with this disease because it has been largely demonstrated that signs of HR are correlated to patient’s health and mortality. Researchers should develop a new common, standardized, and objective method to assess hypertensive retinal changes; new technologies may have a significant role in this field. This review takes most of the literature published so far, including the OCTA studies in order to stimulate new points of reference to standardize parameters and new diagnostic markers of this disease
Deep Learning for ECG Segmentation
We propose an algorithm for electrocardiogram (ECG) segmentation using a
UNet-like full-convolutional neural network. The algorithm receives an
arbitrary sampling rate ECG signal as an input, and gives a list of onsets and
offsets of P and T waves and QRS complexes as output. Our method of
segmentation differs from others in speed, a small number of parameters and a
good generalization: it is adaptive to different sampling rates and it is
generalized to various types of ECG monitors. The proposed approach is superior
to other state-of-the-art segmentation methods in terms of quality. In
particular, F1-measures for detection of onsets and offsets of P and T waves
and for QRS-complexes are at least 97.8%, 99.5%, and 99.9%, respectively.Comment: 10 pages, 7 figure
Magnetism and electronic structure calculation of SmN
The results of the electronic structure calculations performed on SmN by
using the LDA+U method with and without including the spin-orbit coupling are
presented. Within the LDA+U approach, a N(2) band polarization of is induced by Sm(4)-N(2) hybridization, and a half-metallic
ground state is obtained. By including spin-orbit coupling the magnetic
structure was shown to be antiferromagnetic of type II, with Sm spin and
orbital moments nearly cancelling. This results into a semiconducting ground
state, which is in agreement with experimental results.Comment: Submitted to JPCM, 12 pages, 4 figure
DAMA/LIBRA results and perspectives
The DAMA/LIBRA experiment, running at the Gran Sasso National Laboratory of
the I.N.F.N. in Italy, has a sensitive mass of about 250 kg highly radiopure
NaI(Tl). It is mainly devoted to the investigation of Dark Matter (DM)
particles in the Galactic halo by exploiting the model independent DM annual
modulation signature. The present DAMA/LIBRA experiment and the former DAMA/NaI
one (the first generation experiment having an exposed mass of about 100 kg)
have released so far results corresponding to a total exposure of 1.17 ton yr
over 13 annual cycles. They provide a model independent evidence of the
presence of DM particles in the galactic halo at 8.9 sigma C.L.. A short
summary of the obtained results is presented and future perspectives of the
experiment mentioned.Comment: 12 pages, Proceed. of the 15th Bled Workshop "What Comes Beyond
Standard Models" (December 2012), Vol. 13, No.
Requirements of the authorized examinator physician (AME) for class II: interpretative doubts and suggestions
The purpose of this document is to clarify the requirements
that a doctor must have for carrying
out the Authorized Examiner (AME) activity for
class II workers.
We have consulted the normative sources that indicate
the requisite that the authorized physicians
must possess and subsequently we have compared
the norms, the European Union regulations
and the national ones issued by the National Civil
Aviation Body (ENAC), as well as the guidelines
indicated by the EASA.
Finally, Authors give suggestions that can be given
to ENAC regarding the issue of the authorization
as AME examiner for class II workers
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