Tracking atmospheric and riverine terrigenous supplies variability during the last glacial and the Holocene in central Mediterranean

International audienceA multiproxy study coupling mineralogical, grain size and geochemical approaches was used to tentatively retrace eolian and fluvial contributions to sedimentation in the Sicilian Tunisian Strait since the last glacial. The eolian supply is dominant over the whole interval, excepted during the sapropel Si when riverine contribution apparently became significant. Saharan contribution increased during the B011ing Allerod, evidencing the persistence of aridity over North Africa although the northern Mediterranean already experienced moister and warmer conditions. The Younger Dryas is marked by proximal dust inputs, highlighting intense regional eolian activity. A southward migration of dust provenance toward Sahel occurred at the onset of the Holocene, likely resulting from a southward position of the Inter Tropical Convergence Zone that was probably associated with a large-scale atmospheric reorganization. Finally, a peculiar high terrigenous flux associated with drastic modifications of the mineralogical and geochemical sediment signature occurred during the sapropel 51, suggesting the propagation of fine particles derived from major floodings of the Nile River resulting from enhanced rainfall on northeastern Africa and their transportation across the Sicilian Tunisian Strait by intermediate water masses

Metastable Vacua in Superconformal SQCD-like Theories

We study dynamical supersymmetry breaking in vector-like superconformal N=1 gauge theories. We find appropriate deformations of the superpotential to overcome the problem of the instability of the non supersymmetric vacuum. The request for long lifetime translates into constraints on the physical couplings which in this regime can be controlled through efficient RG analysis.Comment: 17 pages, 7 figures, JHEP3.cl

Indications to total thyroidectomy for multinodular goiter in old patients

Background: In Western society, the percentage of elderly people is continually growing. The prevalence of goiter increases with the age and it is estimated that 90% of women over 60 years old and 60% of men over 80 years old have a relief of thyroid nodules. This has great importance for these patients, because the incidence of malignant transformation is higher than younger ones and these are often tumor very aggressive patterns. If thyroidectomy is indicated for patients with suspected neoplasm and severe obstructive symptoms, their surgery should not be delayed since a late urgent operation could raise morbidity and mortality risk. The main indications for young patients are due to obstructive and metabolic causes over and above suspected cancer. Total thyroidectomy is considered by many authors as the treatment of choice. Materials and methods: 75 elderly patients were submitted to thyroidectomy. The indications were metabolic (42.6%), obstructive (32%) and for suspected cancer (25.4%). Results: The most frequent complications observed with respect to young patients in different series have been cardiovascular, pulmonary or urological. Regarding the complications directly related to thyroidectomy, there were no differences compared to younger groups, except transient complications (hypoparathyroidism, seroma). In our experience, the main complication was represented by hypocalcemia (30.6%), permanent in 8% of cases. Cancer was relieved in 21.3% of cases. Prognosis has been excellent in most cases, with immediate remission of symptoms related to thyrotoxicosis and to tracheal and esophageal compression in almost all symptomatic patients. Conclusions: Age is an independent prognostic factor for cancers. It has been demonstrated that elderly patients with PTC that are operated have better prognosis and quality of life due to the resolution of dyspnea and dysphagia. In our experience, we think that age is not a contraindication to thyroid surgery

Infrared stability of ABJ-like theories

We consider marginal deformations of the superconformal ABJM/ABJ models which preserve N=2 supersymmetry. We determine perturbatively the spectrum of fixed points and study their infrared stability. We find a closed line of fixed points which is IR stable. The fixed point corresponding to the ABJM/ABJ models is stable under marginal deformations which respect the original SU(2)xSU(2) invariance, while deformations which break this group destabilize the theory which then flows to a less symmetric fixed point. We discuss the addition of flavor degrees of freedom. We prove that in general a flavor marginal superpotential does not destabilize the system in the IR. An exception is represented by a marginal coupling which mixes matter charged under different gauge sectors. Finally, we consider the case of relevant deformations which should drive the system to a strongly coupled IR fixed point recently investigated in arXiv:0909.2036 [hep-th].Comment: 1+11 pages, 4 figures; v2: minor correction

Energy poverty in Portugal, Italy, and Norway: awareness, short-term driving forces, and barriers in the built environment

Portugal, Italy, and Norway differ by energy performance of buildings and gross domestic product (GDP). Portugal has significantly highest thermal discomfort with harsher winters. In 2021, 80% of Portuguese buildings had a low energy rating, with 75% of buildings without thermal insulation, highly contributing to the energy poverty (EP) of the country. In Italy, despite a generally mild climate, the building stock has low thermal performance. The most affected areas are the suburban and peri-urban ones, with an EP rate in southern regions between 13% and 20% compared to 8.8% at national level. Moreover, 65% of buildings were constructed before the first law on energy saving criteria and a 25% of it has never undergone any work of maintenance or improvement. Norway, despite the limited studies performs well respect to other European Economic Area and European Union countries, in investing and using indicators to enhance and monitor the green energies’ use. Because of energy price growth, seasonal price fluctuations, and different energy tariffs, energy inequality is increasing. EP risk is underestimated, masked by Norway's high GDP and regional price disparity. Energy inequality is increasing due to energy price growth, seasonal price fluctuations, and energy prices’ geographical inequality. The barriers in reducing EP are the underestimation of risk masked by the high GDP, and the need of homogenized prices in Norway. This study provides an overview to discuss EP awareness and it assesses the drivers and barriers that influence building's energy efficiency renovatio

Deglacial and Holocene vegetation and climatic changes in the southern Central Mediterranean from a direct land–sea correlation

International audienceDespite a large number of studies, the long-term and millennial to centennial-scale climatic variability in the Mediterranean region during the last deglaciation and the Holocene is still debated, including in the southern Central Mediterranean. In this paper, we present a new marine pollen sequence (core MD04-2797CQ) from the Siculo-Tunisian Strait documenting the regional vegetation and climatic changes in the southern Central Mediterranean during the last deglaciation and the Holocene. The MD04-2797CQ marine pollen sequence shows that semi-desert plants dominated the vegetal cover in the southern Central Mediterranean between 18.2 and 12.3 ka cal BP, indicating prevailing dry conditions during the deglaciation, even during the Greenland Interstadial (GI)-1. Across the transition Greenland Stadial (GS)-1 -Holocene, Asteraceae-Poaceae steppe became dominant till 10.1 ka cal BP. This record underlines with no chronological ambiguity that even though temperatures increased, deficiency in moisture availability persisted into the early Holocene. Temperate trees and shrubs with heath underbrush or maquis expanded between 10.1 and 6.6 ka, corresponding to Sapropel 1 (S1) interval, while Mediterranean plants only developed from 6.6 ka onwards. These changes in vegetal cover show that the regional climate in southern Central Mediterranean was wetter during S1 and became drier during the mid-to late Holocene. Wetter conditions during S1 were likely due to increased winter precipitation while summers remained dry. We suggest, in agreement with published modeling experiments, that the early Holocene increased melting of the Laurentide Ice Sheet in conjunction with weak winter insolation played a major role in the development of winter precipitation maxima in the Mediterranean region in controlling the strength and position of the North Atlantic storm track. Finally, our data provide evidence for centennial-scale vegetation and climatic changes in the southern Central Mediterranean. During the wet early Holocene, alkenone-derived cooling episodes are synchronous with herbaceous composition changes that indicate muted changes in precipitation. In contrast, enhanced aridity episodes, as detected by strong reduction in trees and shrubs, are recorded during the mid-to late Holocene. We show that the impact of the Holocene cooling events on the Mediterranean hydroclimate depend on baseline climate states, i.e. insolation and ice sheet extent, shaping the response of the mid-latitude atmospheric circulation

Holographic fermions in charged Gauss-Bonnet black hole

We study the properties of the Green's functions of the fermions in charged Gauss-Bonnet black hole. What we want to do is to investigate how the presence of Gauss-Bonnet coupling constant $\alpha$ affects the dispersion relation, which is a characteristic of Fermi or non-Fermi liquid, as well as what properties such a system has, for instance, the Particle-hole (a)symmetry. One important result of this research is that we find for $q=1$, the behavior of this system is different from that of the Landau Fermi liquid and so the system can be candidates for holographic dual of generalized non-Fermi liquids. More importantly, the behavior of this system increasingly similar to that of the Landau Fermi liquid when $\alpha$ is approaching its lower bound. Also we find that this system possesses the Particle-hole asymmetry when $q\neq 0$, another important characteristic of this system. In addition, we also investigate briefly the cases of the charge dependence.Comment: 22 pages, 6 figures; version published in JHE

Z-extremization and F-theorem in Chern-Simons matter theories

The three dimensional exact R symmetry of N=2 SCFTs extremizes the partition function localized on a three sphere. Here we verify this statement at weak coupling. We give a detailed analysis for two classes of models. The first one is an SU(N)_k gauge theory at large k with both fundamental and adjoint matter fields, while the second is a flavored version of the ABJ theory, where the CS levels are large but they do not necessarily sum up to zero. We study in both cases superpotential deformations and compute the R charges at different fixed points. When these fixed points are connected by an RG flow we explicitly verify that the free energy decreases at the endpoints of the flow between the fixed points, corroborating the conjecture of an F-theorem in three dimensions.Comment: 28 pages, 3 figures, JHEP.cls, minor corrections, references adde