A consistent model for leptogenesis, dark matter and the IceCube signal

We discuss a left-right symmetric extension of the Standard Model in which the three additional right-handed neutrinos play a central role in explaining the baryon asymmetry of the Universe, the dark matter abundance and the ultra energetic signal detected by the IceCube experiment. The energy spectrum and neutrino flux measured by IceCube are ascribed to the decays of the lightest right-handed neutrino $N_1$, thus fixing its mass and lifetime, while the production of $N_1$ in the primordial thermal bath occurs via a freeze-in mechanism driven by the additional $SU(2)_R$ interactions. The constraints imposed by IceCube and the dark matter abundance allow nonetheless the heavier right-handed neutrinos to realize a standard type-I seesaw leptogenesis, with the $B-L$ asymmetry dominantly produced by the next-to-lightest neutrino $N_2$. Further consequences and predictions of the model are that: the $N_1$ production implies a specific power-law relation between the reheating temperature of the Universe and the vacuum expectation value of the $SU(2)_R$ triplet; leptogenesis imposes a lower bound on the reheating temperature of the Universe at 7\times10^9\,\mbox{GeV}. Additionally, the model requires a vanishing absolute neutrino mass scale $m_1\simeq0$.Comment: 19 pages, 4 figures. Constraints from cosmic-ray antiprotons and gamma rays added, with hadrophobic assignment of the matter multiplets to satisfy bounds. References added. Matches version published in JHE

IceCube and high-energy neutrinos

The recent IceCube observation of the first high-energy neutrinos has received the PhysicsWorld award for the Breakthrough of the Year 2013. In the light of this important discovery, we revisit the possibility of observing, at the IceCube detector, three Milagro sources: MGRO J2019+37, MGRO J1908+06 and MGRO J2031+41. Moreover, we present a discussion on the possible galactic origin of some of the IceCube events and we comment on the possibility that the high-energy neutrinos detected might come from a Dark Matter decay. Finally, we comment on other important consequences of this discovery, like bounds on Lorentz-invariance violation and on secret neutrino interactions

Statistical tests of sterile neutrinos using cosmology and short-baseline data

In this paper we revisit the question of the information which cosmology provides on the scenarios with sterile neutrinos invoked to describe the SBL anomalies using Bayesian statistical tests. We perform an analysis of the cosmological data in $\Lambda$CDM$+r+\nu_s$ cosmologies for different cosmological data combinations, and obtain the marginalized cosmological likelihood in terms of the two relevant parameters, the sterile neutrino mass $m_s$ and its contribution to the energy density of the early Universe $N_{\rm eff}$. We then present an analysis to quantify at which level a model with one sterile neutrino is (dis)favoured with respect to a model with only three active neutrinos, using results from both short-baseline experiments and cosmology. We study the dependence of the results on the cosmological data considered, in particular on the inclusion of the recent BICEP2 results and the SZ cluster data from the Planck mission. We find that only when the cluster data is included the model with one extra sterile neutrino can become more favoured that the model with only the three active ones provided the sterile neutrino contribution to radiation density is suppressed with respect to the fully thermalized scenario. We have also quantified the level of (in)compatibility between the sterile neutrino masses implied by the cosmological and SBL results.Comment: 23 pages, 4 figure

Tropical forest carbon balance: Effects of field- and satellite-based mortality regimes on the dynamics and the spatial structure of Central Amazon forest biomass

Debate continues over the adequacy of existing field plots to sufficiently capture Amazon forest dynamics to estimate regional forest carbon balance. Tree mortality dynamics are particularly uncertain due to the difficulty of observing large, infrequent disturbances. A recent paper (Chambers et al 2013 Proc. Natl Acad. Sci. 110 3949-54) reported that Central Amazon plots missed 9-17% of tree mortality, and here we address 'why' by elucidating two distinct mortality components: (1) variation in annual landscape-scale average mortality and (2) the frequency distribution of the size of clustered mortality events. Using a stochastic-empirical tree growth model we show that a power law distribution of event size (based on merged plot and satellite data) is required to generate spatial clustering of mortality that is consistent with forest gap observations. We conclude that existing plots do not sufficiently capture losses because their placement, size, and longevity assume spatially random mortality, while mortality is actually distributed among differently sized events (clusters of dead trees) that determine the spatial structure of forest canopies. © 2014 IOP Publishing Ltd

Paratesticular Mesenchymal Malignancies: A Single-Center Case Series, Clinical Management, and Review of Literature

Background: Primary soft tissue sarcomas arising from the male urinary and genital tract are rare tumors, only accounting for 1% to 2% of all malignancies of the genitourinary tract. Clinical management of advanced disease is lacking in standardized recommendations due to the rarity of the disease. To date, complete and extensive surgery represents the only curative and standardized approach for localized disease, while the impact of retroperitoneal lymphadenectomy and adjuvant treatments on clinical outcomes are still unclear. Similarly, a standardized systemic treatment for advanced metastatic disease is still missing. Cases Presentation: Four out of 274 patients have been identified in our sarcoma population. The mean age was 54 years (range = 45-73). The histotypes showed liposarcoma in 2 cases and leiomyosarcoma in the remaining 2 cases. In all 4 cases, the disease was localized at presentation, patients underwent complete surgery, and no adjuvant treatments were done. Three cases presented a recurrence of disease at a mean follow-up of 86 months (range = 60-106 months), more than 7 years. Two cases were treated with a second surgery and chemotherapy and 1 case only with chemotherapy. Discussion and Conclusions: Sharing data about clinical management of paratesticular mesenchymal tumors is a key issue due to the rarity of this tumor\u2019s subtype. In this article, we report the clinical history of 4 patients affected by paratesticular mesenchymal tumor. In particular, main issues of interest are the decision of postoperative treatment and systemic treatment at time of disease recurrence

Comparison of perioperative parameters in one-handed rotational phacoemulsification versus conventional phacoemulsification and femtosecond laser-assisted cataract surgery

AIM: To compare perioperative parameters of one-handed rotational phacoemulsification technique (one-handed phaco-roll) with each of other two techniques, “Divide et Conquer” and femtosecond laser-assisted cataract surgery (FLACS) METHODS: In this retrospective and comparative cohort study, eyes with uncomplicated cataract (nuclear density grade 2 to 3) treated routinely with one-handed phaco-roll (n=23; Group 1) or “Divide et Conquer” (n=23; Group 2) or FLACS (n=23; Group 3) were enrolled. Intraoperative parameters including effective phaco-time (EPt), ultrasound time (USt), aspiration time, surgical time, phacoemulsification (phaco)-power, balanced salt solution (BSS) use, cumulative dissipated energy (CDE) were recorded and compared. Clinical outcomes including best corrected visual acuity (BCVA), corneal endothelial cell density (ECD), endothelial cell loss (ECL), central corneal thickness (CCT) and central macular thickness (CMT), were assessed and compared pre-operatively and at 1mo after surgery. RESULTS: Aspiration and surgical time, and BSS used were lower in Group 1 (P<0.01) than other groups. EPt, phaco-power and CDE were lower in Group 1 (P<0.05) than Group 2 but not significantly different from Group 3. In Group 1, USt was lower (P<0.05) than Group 2 but higher (P<0.05) than Group 3. BCVA improved in all groups without significant difference between Group 1 and the other ones. No significant differences regarding all post-operative morphologic outcomes (ECD, ECL, CCT, CMT) were reported. No clinical complications occurred. CONCLUSION: One-handed phaco-roll seems to be less time-consuming than “Divide et Conquer” and FLACS and less energy-consuming than “Divide et Conquer”. Furthermore, one-handed phaco-roll seems to have an equal safety profile compared to the other two techniques