Multi-momentum and multi-flavour active-sterile neutrino oscillations in the early universe: role of neutrino asymmetries and effects on nucleosynthesis

We perform a study of the flavour evolution in the early universe of a multi-flavour active-sterile neutrino system with parameters inspired by the short-baseline neutrino anomalies. In a neutrino-symmetric bath a "thermal" population of the sterile state would quickly grow, but in the presence of primordial neutrino asymmetries a self-suppression as well as a resonant sterile neutrino production can take place, depending on temperature and chosen parameters. In order to characterize these effects, we go beyond the usual average momentum and single mixing approximations and consider a multi-momentum and multi-flavour treatment of the kinetic equations. We find that the enhancement obtained in this case with respect to the average momentum approximation is significant, up to \sim 20 % of a degree of freedom. Such detailed and computationally demanding treatment further raises the asymmetry values required to significantly suppress the sterile neutrino production, up to large and preferentially net asymmetries |L_{\nu}| > O(10^{-2}). For such asymmetries, however, the active-sterile flavour conversions happen so late that significant distortions are produced in the electron (anti)neutrino spectra. The larger |L_{\nu}|, the more the impact of these distortions takes over as dominant cosmological effect, notably increasing the 4 He abundance in primordial nucleosynthesis (BBN). The standard expression of the primordial yields in terms of the effective number of neutrinos and asymmetries is also greatly altered. We numerically estimate the magnitude of such effects for a few representative cases and comment on possible implications for forthcoming cosmological measurements.Comment: v2 (12 pages, 4 eps figures) revised version. Comments added, references updated. Matches the version published in PR

NMR Structure and CD Titration with Metal Cations of Human Prion α2-Helix-Related Peptides

The 173–195 segment corresponding to the helix 2 of the C-globular prion protein domain could be one of several “spots” of intrinsic conformational flexibility. In fact, it possesses chameleon conformational behaviour and gathers several disease-associated point mutations. We have performed spectroscopic studies on the wild-type fragment 173–195 and on its D178N mutant dissolved in trifluoroethanol to mimic the in vivo system, both in the presence and in the absence of metal cations. NMR data showed that the structure of the D178N mutant is characterized by two short helices separated by a kink, whereas the wild-type peptide is fully helical. Both peptides retained these structural organizations, as monitored by CD, in the presence of metal cations. NMR spectra were however not in favour of the formation of definite ion-peptide complexes. This agrees with previous evidence that other regions of the prion protein are likely the natural target of metal cation binding

Light sterile neutrino production in the early universe with dynamical neutrino asymmetries

Light sterile neutrinos mixing with the active ones have been recently proposed to solve different anomalies observed in short-baseline oscillation experiments. These neutrinos can also be produced by oscillations of the active neutrinos in the early universe, leaving possible traces on different cosmological observables. Here we perform an updated study of the neutrino kinetic equations in (3+1) and (2+1) oscillation schemes, dynamically evolving primordial asymmetries of active neutrinos and taking into account for the first time CP-violation effects. In the absence of neutrino asymmetries, eV-mass scale sterile neutrinos would be completely thermalized creating a tension with respect to the CMB, LSS and BBN data. In the past literature, active neutrino asymmetries have been invoked as a way to inhibit the sterile neutrino production via the in-medium suppression of the sterile-active mixing angle. However, neutrino asymmetries also permit a resonant sterile neutrino production. We find that if the active species have equal asymmetries L, a value |L|=10^{-3} is required to start suppressing the resonant sterile production, roughly an order of magnitude larger than what previously expected. When active species have opposite asymmetries the sterile abundance is further enhanced, requiring an even larger |L|\simeq 10^{-2} to start suppressing their production. In the latter case, CP-violation (naturally expected) further exacerbates the phenomenon. Some consequences for cosmological observables are briefly discussed: for example, it is likely that moderate suppressions of the sterile species production are associated with significant spectral distortions of the active neutrino species, with potentially interesting phenomenological consequences especially for BBN.Comment: (v2: 22 pages, 10 eps figures. Revised version. Typos removed, reference updated. Matches the version published on PRD.

Vox clamantis in deserto: a survey among Italian psychiatrists on defensive medicine and professional liability

Due to recent events, professional liability for psychiatrists in Italy is currently a matter of lively debate. Specifically, overwhelming pressure on psychiatrists’ duties has been brought by regulatory developments, such as the closure of forensic psychiatric hospitals, with the consequent return of offenders to community-based care, and the mental health consequences of the pandemic. According to Italian courts, psychiatrists are not only responsible for diagnostic and therapeutic appropriateness but also for the effects of their interventions on patients, and their behaviors. The aim of this study was to explore the attitude and behaviors of Italian psychiatrists regarding defensive medicine and professional liability. A total sample of 254 psychiatrists was surveyed by means of a quantitative online questionnaire. Most psychiatrists reported practicing defensive medicine (no. 153/254, 60.2%) and felt that their position of guarantee compromised their work in healthcare for patients (no. 138/253, 54.3%). Age correlated inversely with acknowledgment of defensive practices (r = −0.245, p < 0.001), with younger physicians more prone to defensive medicine (p = 0.013), particularly for patients at risk of suicide or violence. Psychiatrists in ‘closed’ settings (hospital wards, residential and rehabilitation centers, mental health service units in prison) reported more malpractice claims (p = 0.037) and complaints (p = 0.031), as well as a greater propensity to act defensively. In the treatment of patients with violent behavior, suicidal ideation, dual diagnoses, and criminal convictions, defensive practices were associated more with perceived legal risks (r = 0.306, p < 0.001) than actual legal involvement (p > 0.05). Anxiety, anger, and restlessness were common reactions to legal complaints, involving no. 50/254 (19.7%) respondents, with 40% reporting impaired functioning. Most psychiatrists (no. 175/253, 68.9%) were concerned about both civil and criminal laws regarding their professional responsibility, but many were not fully informed about recent legislative regulations and younger physicians resulted scarcely trained in risk management (p < 0.001). In conclusion, our findings suggest that defensive medicine is a common phenomenon among psychiatrists and their position of guarantee drives this attitude. Education on legal implications and risk management should be provided starting from the university and continuing over time, to improve the knowledge of young and senior doctors on professional liability and inform their decision-making processes. This would also reduce defensive practices and improve the quality of healthcare. Considering the concerns of younger physicians, as well as of professionals working in acute and high-intensity medical care facilities, there is also an urgent need for a revision of the medical liability to ensure the sustainability of the National Health Service

Screening for cervical carcinoma in HIV-infected women: Analysis of main risk factors for cervical cytologic abnormalities

AIM: The aim of this study was to identify potential predictive factors for cervical disease in women with HIV and to evaluate adherence during follow-up to cervical cancer screening. METHODS: In order to identify the independent role of factors associated with the presence of a cervical abnormality, all of the variables showing in univariate analyses a potential association with the outcome variable (presence of cervical abnormalities) were entered into a multivariate logistic regression model, along with age at first visit to our center, and age at diagnosis. RESULTS: A total of 540 HIV-positive women who received screening for cervical cancer during the first year after their first visit to our center were included in the analysis; 423 (78.3%) had normal cytology and 117 (21.7%) had cytological abnormalities, classified as follows: 21 atypical squamous cells of undetermined significance (17.9%); 51 low-grade squamous intraepithelial lesions (43.6%); 41 high-grade squamous intraepithelial lesions (35.0%); and four cervical cancers (3.4%). In our study, women with more than two previous pregnancies were significantly associated with a lower risk of cervical cytological abnormalities compared to the other women. Women with CD4+ levels of 200-499/mm3 had a higher risk of developing cervical cytological abnormalities compared to those with a CD4+ level > 500/ mm3 . CONCLUSION: In summary, management of HIV-positive women must be modeled on HIV-clinical status, CD4+ cell count, drug regimen, and adherence to follow-up, relying on the cooperation of highly qualified professionals. In HIV-positive women, an adequate screening and follow-up allows for a reduced occurrence of advanced cervical disease and prevents recourse to invalidating surgical interventions

A New Orbiting Deployable System for Small Satellite Observations for Ecology and Earth Observation

In this paper, we present several study cases focused on marine, oceanographic, and atmospheric environments, which would greatly benefit from the use of a deployable system for small satellite observations. As opposed to the large standard ones, small satellites have become an effective and affordable alternative access to space, owing to their lower costs, innovative design and technology, and higher revisiting times, when launched in a constellation configuration. One of the biggest challenges is created by the small satellite instrumentation working in the visible (VIS), infrared (IR), and microwave (MW) spectral ranges, for which the resolution of the acquired data depends on the physical dimension of the telescope and the antenna collecting the signal. In this respect, a deployable payload, fitting the limited size and mass imposed by the small satellite architecture, once unfolded in space, can reach performances similar to those of larger satellites. In this study, we show how ecology and Earth Observations can benefit from data acquired by small satellites, and how they can be further improved thanks to deployable payloads. We focus on DORA—Deployable Optics for Remote sensing Applications—in the VIS to TIR spectral range, and on a planned application in the MW spectral range, and we carry out a radiometric analysis to verify its performances for Earth Observation studies

Morphologic alterations in the cilia of a cat.

Based upon ultrastructural findings and computed tomography, a presumptive diagnosis of feline primary ciliary dyskinesia was made in a 2.5-year-old cat. The cat demonstrated morphologic alterations in the ultrastructure of oviductal cilia. In the oviduct, axonemal abnormalities were detected in 132 (20%) of 660 cross-sectioned cilia. The main ultrastructural ciliary defects were a lack of central microtubules, transposition of peripheral doublets to the center of the axoneme, supernumerary microtubules, and morphologic abnormalities of peripheral doublets. Computed tomography of the chest was consistent with early lesions of bronchiectasis, suggesting chronic stagnation of respiratory secretions, attributed to abnormal function of respiratory cilia. Specifically, the cranial branches of the cat's bronchi were wider and thicker than those of five healthy controls. Foci of pleural thickening and interstitial enlargement were also observed

Massive sterile neutrinos in the early Universe: From thermal decoupling to cosmological constraints

International audienceWe consider relatively heavy neutrinos νH, mostly contributing to a sterile state νs, with mass in the range 10  MeV≲ms≲mπ∼135  MeV, which are thermally produced in the early Universe in collisional processes involving active neutrinos and freezing out after the QCD phase transition. If these neutrinos decay after the active neutrino decoupling, they generate extra neutrino radiation but also contribute to entropy production. Thus, they alter the value of the effective number of neutrino species Neff as, for instance, measured by the cosmic microwave background (CMB), as well as affect primordial nucleosynthesis (BBN), notably He4 production. We provide a detailed account of the solution of the relevant Boltzmann equations. We also identify the parameter space allowed by current Planck satellite data and forecast the parameter space probed by future stage-4 ground-based CMB observations, expected to match or surpass BBN sensitivity