Electromagnetic signals from bare strange stars

Strange stars with a crystalline color superconducting crust can sustain large shear stresses, supporting torsional oscillations of large amplitude. We consider a simple model of strange star with a bare quark matter surface. When a torsional oscillation is excited, for example by a stellar glitch, the positive charge at the star surface oscillates, with typical kHz frequencies, for a 1km thick crust, to hundreds of Hz, for a 9km thick crust. Higher frequencies, of the order of few GHz, can be reached if the star crust is of the order of few centimeters thick. The estimated emitted power is of the order of 1045 erg/s

Politicians “on board”! Do political connections affect banking activities in Italy?

This paper analyzes the effects of political presence in the boards of directors of cooperative banks. We refer our analysis to all politicians (almost 160.000) belonging to a political body in Italy. Overall, our dataset contains 1.858 board members referring to 127 cooperative banks. Results show that politically connected banks, in which politicians have executive roles in the board of directors, display higher net interest revenues, lower quality of the loans portfolio and lower efficiency relative to a control group of non-connected counterparts. Therefore, in the current debate on the reform of the statutes of the Italian cooperative banks, we argue that the problem is not for politicians to be in the boards but for them to hold executive positions.Cooperative Banks, Politics, Corporate Governance

Hydrocomplexity, and spatial and time scales as drivers of monitoring and management approaches for a karst coastal aquifer (Salento, southern Italy)

Hydrogeological scenario, Salento aquifer, monitoring wells

Pain perception and migraine

Background: It is well-known that both inter-and intra-individual differences exist in the perception of pain; this is especially true in migraine, an elusive pain disorder of the head. Although electrophysiology and neuroimaging techniques have greatly contributed to a better understanding of the mechanisms involved in migraine during recent decades, the exact characteristics of pain threshold and pain intensity perception remain to be determined, and continue to be a matter of debate.Objective: The aim of this review is to provide a comprehensive overview of clinical, electrophysiological, and functional neuroimaging studies investigating changes during various phases of the so-called "migraine cycle" and in different migraine phenotypes, using pain threshold and pain intensity perception assessments.Methods: A systematic search for qualitative studies was conducted using search terms "migraine," "pain," "headache," "temporal summation," "quantitative sensory testing," and "threshold," alone and in combination (subject headings and keywords). The literature search was updated using the additional keywords "pain intensity," and "neuroimaging"to identify full-text papers written in English and published in peer-reviewed journals, using PubMed and Google Scholar databases. In addition, we manually searched the reference lists of all research articles and review articles.Conclusion: Consistent data indicate that pain threshold is lower during the ictal phase than during the interictal phase of migraine or healthy controls in response to pressure, cold and heat stimuli. There is evidence for preictal sub-allodynia, whereas interictal results are conflicting due to either reduced or no observed difference in pain threshold. On the other hand, despite methodological limitations, converging observations support the concept that migraine attacks may be characterized by an increased pain intensity perception, which normalizes between episodes. Nevertheless, future studies are required to longitudinally evaluate a large group of patients before and after pharmacological and non-pharmacological interventions to investigate phases of the migraine cycle, clinical parameters of disease severity and chronic medication usage

"EEG abnormalities" may represent a confounding factor in celiac disease. A 4-year follow-up family report

Objective: The occurrence of celiac disease (CD), electroencephalographic (EEG) abnormalities (with "subtle" seizures or even without any clinical seizures), and neurological disorders has been reported since the 1980s, though there has been no definitive consensus about the possible causal relationship. This topic is further complicated by the occurrence in infancy of 'clinical-EEG pictures' called 'benign epilepsy of infancy'. Methods and results: Here, we report a 4-year follow-up on two siblings with newly diagnosed biopsy-proven celiac disease showing EEG abnormalities not responsive to a gluten-free diet. Conclusions: This family report indicates that in patients with neurologically asymptomatic CD and EEG abnormalities, it is advisable to make a differential diagnosis between EEG abnormalities associated with CD and an incidental association with cortical hyperexcitability, with "subtle" seizures or even without any clinical seizures. Practice implications: A long follow-up may sometimes be required, as it was in the family described here, to clarify the etiopathogenetic and therapeutic relationships between clinical and EEG features in CD

Four-year follow-up study in a NF1 Boy with a focal pontine hamartoma

Neurofibromatosis is a collective name for a group of genetic conditions in which benign tumours affect the nervous system. Type 1 is caused by a genetic mutation in the NF1 gene (OMIM 613113) and symptoms can vary dramatically between individuals, even within the same family. Some people have very mild skin changes, whereas others suffer severe medical complications. The condition usually appears in childhood and is diagnosed if two of the following are present: six or more café-au-lait patches larger than 1.5 cm in diameter, axillary or groin freckling, 2 or more Lisch nodules (small pigmented areas in the iris of the eye), 2 or more neurofibromas, optic pathway gliomas, bone dysplasia, and a first-degree family relative with Neurofibromatosis type 1. The pattern of inheritance is autosomal dominant, however, half of all NF1 cases are 'sporadic' and there is no family history. Neurofibromatosis type 1 is an extremely variable condition whose morbidity and mortality is largely dictated by the occurrence of the many complications that may involve any of the body systems. We describe a family affected by NF1 in whom genetic molecular analysis identified the same mutation in the son and father. Routine MRI showed pontine focal lesions in the eight-year-old son, though not in the father. We performed a four years follow-up study and at follow-up pontine hamartoma size remained unchanged in the son, and the father showed still no brain lesions, confirming thus an intra-familial phenotype variability

New totally intracorporeal reconstructive approach after robotic total gastrectomy. Technical details and short-term outcomes

AIM: To show outcomes of our series of patients that underwent a total gastrectomy with a robotic approach and highlight the technical details of a proposed solution for the reconstruction phase. METHODS: Data of gastrectomies performed from May 2014 to October 2016, were extracted and analyzed. Basic characteristics of patients, surgical and clinical outcomes were reported. The technique for reconstruction (Parisi Technique) consists on a loop of bowel shifted up antecolic to directly perform the esophago-enteric anastomosis followed by a second loop, measured up to 40 cm starting from the esojejunostomy, fixed to the biliary limb to create an enteroenteric anastomosis. The continuity between the two anastomoses is interrupted just firing a linear stapler, so obtaining the Roux-en-Y by avoiding to interrupt the mesentery. RESULTS: Fifty-five patients were considered in the present analysis. Estimated blood loss was 126.55 ± 73 mL, no conversions to open surgery occurred, R0 resections were obtained in all cases. Hospital stay was 5 (3-17) d, no anastomotic leakage occurred. Overall, a fast functional recovery was shown with a median of 3 (3-6) d in starting a solid diet. CONCLUSION: Robotic surgery and the adoption of a tailored reconstruction technique have increased the feasibility and safety of a minimally invasive approach for total gastrectomy. The present series of patients shows its implementation in a western center with satisfying short-term outcomes

Thermo-Mechanical and Morphological Properties of Polymer Composites Reinforced by Natural Fibers Derived from Wet Blue Leather Wastes: A Comparative Study

The present work investigated the possibility to use wet blue (WB) leather wastes as natural reinforcing fibers within different polymer matrices. After their preparation and characterization, WB fibers were melt-mixed at 10 wt.% with poly(lactic acid) (PLA), polyamide 12 (PA12), thermoplastic elastomer (TPE), and thermoplastic polyurethane (TPU), and the obtained samples were subjected to rheological, thermal, thermo-mechanical, and viscoelastic analyses. In parallel, morphological properties such as fiber distribution and dispersion, fiber–matrix adhesion, and fiber exfoliation phenomena were analyzed through a scanning electron microscope (SEM) and energy-dispersive spectroscopy (EDS) to evaluate the relationship between the compounding process, mechanical responses, and morphological parameters. The PLA-based composite exhibited the best results since the Young modulus (+18%), tensile strength (+1.5%), impact (+10%), and creep (+5%) resistance were simultaneously enhanced by the addition of WB fibers, which were well dispersed and distributed in and significantly branched and interlocked with the polymer matrix. PA12- and TPU-based formulations showed a positive behavior (around +47% of the Young modulus and +40% of creep resistance) even if the not-optimal fiber–matrix adhesion and/or the poor de-fibration of WB slightly lowered the tensile strength and elongation at break. Finally, the TPE-based sample exhibited the worst performance because of the poor affinity between hydrophilic WB fibers and the hydrophobic polymer matrix