Supersymmetric type-III seesaw: lepton flavour violating decays and dark matter

We study a supersymmetric version of the seesaw mechanism type-III. The model consists of the MSSM particle content plus three copies of 24 superfields. The fermionic part of the SU(2) triplet contained in the 24 is responsible for the type-III seesaw, which is used to explain the observed neutrino masses and mixings. Complete copies of 24 are introduced to maintain gauge coupling unification. These additional states change the beta functions of the gauge couplings above the seesaw scale. Using mSUGRA boundary conditions we calculate the resulting supersymmetric mass spectra at the electro-weak scale using full 2-loop renormalization group equations. We show that the resulting spectrum can be quite different compared to the usual mSUGRA spectrum. We discuss how this might be used to obtain information on the seesaw scale from mass measurements. Constraints on the model space due to limits on lepton flavour violating decays are discussed. The main constraints come from the bounds on the decay mu to e and gamma but there are also regions where the decay tau to mu and gamma gives stronger constraints. We also calculate the regions allowed by the dark matter constraint. For the sake of completeness, we compare our results with those for the supersymmetric seesaw type-II and, to some extent, with type-I.Comment: 32 pages, 16 eps figures. One ref. added; small changes in tex

Electrochemical degradation of reactive blue 19 dye in textile wastewater

Textile wastewater is notoriously known to contain strong colour, a highly fluctuating pH and significant COD (Chemical Oxygen Demand) values. Because of these characteristics, treatment of these effluents has been rather difficult. Traditional methods for dealing with textile wastewater consist of various combinations of biological, physical and chemical methods. Because of the large variability of the composition of textile wastewaters, most of these traditional methods are becoming inadequate. The aim of this work was to use an electrochemical procedure to treat used dyebaths and cyclic voltammetry (CV) technique for dye degradation study. Electrolysis can be an adequate process for colour removal as well organics pollutants and CV is an important tool for redox reactions interpretation. Electrochemical treatment results show significant decrease on COD values, for the different values of dye concentration and several applied potentials. Progressive colour removal and dye degradation can be achieved for different values of dye concentration. Depending on electrolysis time and applied potential, total decolouration can be attained

Carbon Materials Derived from Cyano-Based IL@ZIF-8 Composites for CO2 Sorption Separation Systems

Additionally, this work was partially supported by the Asso- ciate Laboratory for Green Chemistry, LAQV, which is funded by national funds from FCT/MCTES (LA/P/00 08/2020) .The sorption capacity and selectivity of pre- and post-carbonized cyano-based metal-organic framework (MOF) composite materials (cyano-based IL@ZIF-8) were investigated for the first time. The influence of the ionic liquid (IL) loading and number of cyano groups in the IL anion on a materials gas sorption separation performance was studied. Sorption-desorption equilibrium isotherms of CO2, CH4, and N2 were measured at 303 K in the ZIF-8, cyano-based IL@ZIF-8 composites and their derived carbon materials. The IL loading did not significantly affect the gas uptake of the carbon materials, while for the composites its main contribution was on the increase of the selectivity. The number of cyano groups in the anion played a key role in the sorption capacity and selectivity performance as it directly affects the N content and textural properties. The carbon material obtained from ZIF-8 (C_ZIF-8) precursor showed the best sorption capacity for all gases, just being surpassed by the C_15%[C6MIM][B(CN)4]@ZIF-8 carbon up to 1 bar. In terms of selectivity performance, carbons based on [C6MIM][B(CN)4]@ZIF-8 composites revealed to be equally or more selective than C_ZIF-8, increasing up to 65% between 0 and 1 bar depending on the mixture. The composites produced and their respective carbons demonstrated a promising application as sorbents for post-combustion CO2 separation systems.publishersversionpublishe

Unveiling the Temperature Influence on the Sorptive Behaviour of ZIF-8 Composite Materials Impregnated with [Cn MIM][B(CN)4 ] Ionic Liquids

LA/P/0008/2020 PTDC/CTM-CTM/ 30326/2017Composite sorbent materials (IL@MOF) with a metal-organic framework (MOF) ZIF-8 and [B(CN)4 ]−-based ionic liquids (ILs) were produced for the first time. Characterization results indicate the successful IL impregnation and conservation of the ZIF-8 crystalline structure and morphology. The data collected from the nitrogen (N2 ) physisorption at 77 K suggest that these IL@ZIF-8 materials are nonporous as their textural properties, such as BET specific surface area and total pore volume, are negligible. However, CO2, CH4, and N2 adsorption/desorption measurements in the IL@ZIF-8 composites at 303 and 273 K contradict the N2 data at 77 K, given that the obtained isotherms are Type I, typical of (micro)porous materials. Their gas adsorption capacity and ultramicroporous volume are in the same order of magnitude as the pristine microporous ZIF-8. The case study [C6 MIM][B(CN)4 ] IL revealed a high affinity to both CO2 and CH4 . This compromised the selectivity performance of its respective composite when compared with pristine ZIF-8. This work highlights the importance of accurate experimental gas adsorption/desorption equilibrium measurements to characterize the adsorption uptake and the porous nature of adsorbent materials.publishersversionpublishe

Metastatic Testicular Germ Cell Tumor or a Chemoresponsive Liver Hemangioma?

Testicular germ cell tumors are the most common solid organ malignancy in young adult men. The presence of non-pulmonary visceral metastasis is an independent factor that places such patients into the higher risk group. Hepatic hemangiomas are the most common tumors of the liver and are entirely benign. Overlap between these entities may occur, particularly when metastases are hypervascular. We describe a case of a 27-year-old man with a testicular germ cell tumor and a nodule in the right hepatic lobe suggestive of hemangioma. After three cycles of chemotherapy, a size reduction in the hepatic nodule was confirmed, and this lesion was removed. Pathology revealed a fibrosing hemangioma. In this case report, the authors discuss the possible mechanisms for the hemangioma chemotherapy response

Benthic macro-invertebrates as indicators of ecological fragility of small rivers ('igarapés') in a bauxite mining region of Brazilian Amazonia

Benthic macroinvertebrate communities were studied in the igarapés Saracá, Caranã and Água Fria near Porto Trombetas, Municipality of Oriximiná, State of Pará, Brazil (1°25' to 1°35'S and 56°15' to 56°W). The main objective was to investigate the potential use of the benthic macroinvertebrates community as indicators of the ecological fragility of the igarapés located in an area of the Amazon basin influenced by bauxite mining. These aquatic ecosystems have low pH (< 4.5); low electrical conductivity (< 90 µS cm-1); low or undetectable total alkalinity; low nutrient concentrations in the sediment, which implies low primary productivity; low species richness; low secondary productivity; and low rates of organic matter decomposition. The benthic macroinvertebrates utilize mainly allochthonous organic matter. Some areas of the ecosystems investigated have been modified by bauxite tailings (especially in their sediment granulometry), by a dam formed by railroad construction (which altered the hydrodynamics and eliminated the terra firma vegetation), and by accidental discharges of various minerals from the railroad traffic and bauxite mining. These factors have drastically modified the local benthic macroinvertebrate communities. The value of benthic macroinvertebrates as indicators of ecological fragility, the health of the ecosystem investigated, and water quality is evaluated

Lepton flavor violation in SUSY left-right symmetric theories

The seesaw mechanism is the most popular explanation for the smallness of neutrino masses. However, its high scale makes direct tests impossible and only indirect signals at low energies are reachable for collider experiments. One of these indirect links with the high scale is lepton flavor violation (LFV). We discuss LFV decays of sleptons in the context of a SUSY left-right symmetric model that naturally incorporates the seesaw mechanism. This non-minimal embedding of the seesaw leads to observable LFV effects in the right-handed sleptons sector, contrary to minimal models where these are found to be totally negligible. Therefore, LFV observables can be used as a powerful tool to study physics right below the GUT scale.Comment: To appear in the proceedings of PASCOS 2010, the 16th International Symposium on Particles, Strings and Cosmology, Valencia, Spai

Living with hearing loss: psychosocial impact and the role of social support

Background: Hearing loss is one of the most common diseases affecting older occupying the 10th place among the diseases with greatest influence in human life conditions, and in Portugal it is considered the 5th main cause of suffering in this population. Objectives: The present study was designed to evaluate the psychosocial impact (daily activities, social activities, general emotional state) of this disease as a function of the hearing loss degree (mild, moderate or severe)On the other hand, considering the protector role that social support (instrumental and informational) can play in chronic diseases, we analyzed the moderation role of variable in the relation between hearing loss and negative emotional symptoms (anxiety, depression and stress). Methods: One hundred and ten patients with a hearing loss diagnosed, with a mean age of 70 years old (SD=7.89) participated in the study. Self report measures of social support and emotional distress were administered and sociodemographic characteristics were collected. Results: In general, the results showed that hearing loss has a negative role in daily and social activities as well as in the general emotional state of these patients. Nevertheless, for negative emotional states such as anxiety, depression and stress, the instrumental support had a buffering effect, since independently from the hearing loss degree, higher social support was associated with lower levels of anxiety, depression and stress. Conclusions: Overall, the results contribute to enhance the protective role that social support might have in chronic diseases and particularly in hearing loss.info:eu-repo/semantics/publishedVersio

A_4-based neutrino masses with Majoron decaying dark matter

We propose an A_4 flavor-symmetric SU(3)xSU(2)xU(1) seesaw model where lepton number is broken spontaneously. A consistent two-zero texture pattern of neutrino masses and mixing emerges from the interplay of type-I and type-II seesaw contributions, with important phenomenological predictions. We show that, if the Majoron becomes massive, such seesaw scenario provides a viable candidate for decaying dark matter, consistent with cosmic microwave background lifetime constraints that follow from current WMAP observations. We also calculate the sub-leading one-loop-induced decay into photons which leads to a mono-energetic emission line that may be observed in future X-ray missions such as Xenia.Comment: 16 pages, 6 eps figures. Minor corrections. To appear in Phys. Rev.