Current-induced spin polarization in InGaAs and GaAs epilayers with varying doping densities

The current-induced spin polarization and momentum-dependent spin-orbit field were measured in In$_{x}$Ga$_{1-x}$As epilayers with varying indium concentrations and silicon doping densities. Samples with higher indium concentrations and carrier concentrations and lower mobilities were found to have larger electrical spin generation efficiencies. Furthermore, current-induced spin polarization was detected in GaAs epilayers despite the absence of measurable spin-orbit fields, indicating that the extrinsic contributions to the spin polarization mechanism must be considered. Theoretical calculations based on a model that includes extrinsic contributions to the spin dephasing and the spin Hall effect, in addition to the intrinsic Rashba and Dresselhaus spin-orbit coupling, are found to qualitatively agree with the experimental results.Comment: 16 pages, 8 figure

INTEGRATED ANALYSIS OF GROUND DISPLACEMENT DATA, SEISMIC ACTIVITY AND MORPHOMETRIC DATA OF THE CAMPI FLEGREI (CAMPANIA, SOUTHERN ITALY) 2000-2006 RECENT BRADYSEISMIC CRISES, IN GIS ENVIRONMENT.

In this paper the results of an integrated analysis of ground displacement data, local seismic activity and DEM image analysis, in GIS environment, which has been performed for the Campi Flegrei volcanic area, are presented and discussed. The study has been carried out for the recent bradyseismic crises of 2000-2006, with the aim of working out a preliminary interpretation of the recent dynamics of the area

Clinical pathways of epileptic seizures and status epilepticus: results from a survey in Italy

Objective: Patients with seizures or status epilepticus (SE) access the hospital through emergency departments and may be admitted into different wards according to the level of care required. Clinicians with different expertise are in charge of taking critical therapeutic decisions. To date, very few studies have investigated the stage at which these patients are referred to neurologists or epileptologists and how guideline recommendations are applied in clinical practice. Methods: A survey was used to investigate how patients with epileptic seizures or SE are managed in emergency and in subsequent hospital pathways in Italy. Results: One hundred and seventy-seven physicians (mainly neurologists) from all parts of Italy filled in a questionnaire. Less than half of the participants (35%) answered that, in their hospital, patients with epilepsy were managed by epileptologists. The percentages were lower for patients presenting with acute seizures (21%) or SE (16%). Diagnostic, therapeutic, and assistance pathways (PDTA) for patients presenting with seizure(s) or SE were available for both conditions in about 50% of cases, while, in the rest of the hospitals, participants indicated informal agreements (about 25% of cases) or lack of any agreement (about 25% of cases) between clinicians. Professionals more often involved in PDTA were epileptologists/neurologists, emergency physicians, and intensivists. More than half ot the participants (55%) thought that organizational issues are the most important criticalities for such patients and need to be improved (61%). Significance: There is a high variability in hospital clinical pathways for epilepsy in Italy

Frictional melting of peridotite and seismic slip

The evolution of the frictional strength along a fault at seismic slip rates (about 1 m/s) is a key factor controlling earthquake mechanics. At mantle depths, friction-induced melting and melt lubrication may influence earthquake slip and seismological data. We report on laboratory experiments designed to investigate dynamic fault strength and frictional melting processes in mantle rocks. We performed 20 experiments with Balmuccia peridotite in a high-velocity rotary shear apparatus and cylindrical samples (21.8 mm in diameter) over a wide range of normal stresses (5.4–16.1 MPa), slip rates (0.23–1.14 m/s), and displacements (1.5–71 m). During the experiments, shear stress evolved with cumulative displacement in five main stages (stages 1–5). In stage 1 (first strengthening), the coefficient of friction m increased up to 0.4–0.7 (first peak in friction). In stage 2 (abrupt firstweakening), m decreased to about 0.25–0.40. In stage 3 (gradual second strengthening), shear stress increased toward a second peak in friction (m = 0.30–0.40). In stage 4 (gradual second weakening), the shear stress decreased toward a steady state value (stage 5) with m = 0.15. Stages 1 and 2 are of too short duration to be investigated in detail with the current experimental configuration. By interrupting the experiments during stages 3, 4, and 5, microstructural (Field Emission Scanning Electron Microscope) and geochemical (Electron Probe Micro-Analyzer and Energy Dispersive X-Ray Spectroscopy) analysis of the slipping zone suggest that second strengthening (stage 3) is associated with the production of a grain-supported melt-poor layer, while second weakening (stage 4) and steady state (stage 5) are associated with the formation of a continuous melt-rich layer with an estimated temperature up to 1780 C. Microstructures formed during the experiments were very similar to those found in natural ultramafic pseudotachylytes. By performing experiments at different normal stresses and slip rates, (1) the ‘‘thermal’’ (as it includes the thermally activated first and second weakening) slip distance to achieve steady state from the first peak in strength decreased with increasing normal stress and slip rate and (2) the steady state shear stress slightly increased with increasing normal stress and, for a given normal stress, decreased with increasing slip rate. The ratio of shear stress versus normal stress was about 0.15, well below the typical friction coefficient of rocks (0.6–0.8). The dependence of steady state shear stress with normal stress was described by means of a constitutive equation for melt lubrication. The presence of microstructures similar to those found in natural pseudotachylytes and the determination of a constitutive equation that describes the experimental data allows extrapolation of the experimental observations to natural conditions and to the study of rupture dynamics in mantle rocks

Characterising plasticised cellulose acetate-based historic artefacts by NMR spectroscopy: a new approach for quantifying the degree of substitution and diethyl phthalate contents

As one of the first semi-synthetic plastics produced industrially, cellulose acetate (CA)-based artefacts represent valued items in museum collections and archives which, however, present stability issues. High temperature and relative humidity conditions have long been known to promote changes in CA properties, for instance, due to the deacetylation of CA polymer chains and the loss of plasticiser from the polymer matrix. However, there is a need for improved methods for the quantification of plasticiser loss and CA deacetylation. In this context, this contribution presents a new approach for enabling the investigation of plasticiser loss and deacetylation degradation processes in historic plasticised CA-based artefacts which is based on high-resolution proton nuclear magnetic resonance spectroscopy (1H NMR). The proposed methods allow for simple and fast quantification of diethyl phthalate contents and average degree of substitution (DS), while requiring no need for extractive separation between the plasticiser and the CA polymer matrix prior to analysis. Both methods are demonstrated by their application towards a series of reference samples, historic artefacts and artificially aged plasticised CA materials. Our analysis indicates that plasticiser content and DS can be accurately quantified by using high-resolution 1H NMR and both methods have been compared to analyses performed using infrared spectroscopy

Emergency laparotomy for misdiagnosed biliary cystadenoma originating from caudate lobe

BACKGROUND: Biliary cystadenoma is a rare benign neoplasm, which is often misdiagnosed for a hepatic abscess or a hydatid cyst that tends to recur and is at risk for progression to malignant neoplasm. CASE PRESENTATION: This case describes a 30-year-old woman admitted to our institution in an emergency setting. The patient was originally misdiagnosed as affected by a hepatic hydatid cyst at another hospital, and then emergently treated at our Institution for severe abdominal pain. Histologic evaluation of the cyst showed that it was a biliary cystadenoma and, therefore, the patient underwent a hepatic resection in order to completely remove the lesion. CONCLUSION: Complete excision of any suspicious hepatic cystic lesion remains the best method for diagnosis and treatment of cystadenoma. Incomplete excision of most biliary cystadenoma results in a higher rate of recurrence and the risk of malignant transformation. We report this case to elucidate the clinical presentation, preoperative evaluation, and surgical treatment of these rare lesions

Effects of Direct-Acting Antiviral Agents on the Mental Health of Patients with Chronic Hepatitis C: A Prospective Observational Study

In chronic hepatitis C (CHC) patients, interferon-based treatments showed toxicity, limited e cacy, and psychiatric manifestations. Direct-acting antiviral (DAA) agents appeared safer, though it remains unclear if they may exacerbate or foster mood symptoms in drug-naïve CHC patients. We evaluated 62 CHC patients’ mental status, before and 12 weeks after DAA therapy, by assessment scales and psychometric instruments. We subdivided patients into two groups, CHC patients with (Group A) or without (Group B) a current and/or past psychiatric history. After DAA treatment, Group A patients showed low anxiety and improved depression, no variation in self-report distress, but worse general health perceptions. No significant di erence emerged from coping strategies. Depression and anxiety improved in Group B, and no change emerged from total self-reported distress, except for somatization. Moreover, Group B increased problem-focused strategies for suppression of competing activities, and decreased strategies of instrumental social support. Contrarily, Group B reduced significantly emotion-focused strategies, such as acceptance and mental disengagement, and improved vitality, physical and social role functioning. DAA therapy is safe and free of hepatological and psychiatric side e ects in CHC patients, regardless of current and/or past psychiatric history. In particular, patients without a psychiatric history also remarkably improved their quality of life

Fournier's gangrene and intravenous drug abuse. An unusual case report and review of the literature

Fournier's gangrene is a potentially fatal emergency condition characterized by necrotizing fasciitis and supported by an infection of the external genital, perineal and perianal region, with a rapid and progressive spread from subcutaneous fat tissue to fascial planes.In this case report, a 52-year-old man, with a history of hepatitis C-virus (HCV)-related chronic liver disease and cocaine use disorder for which he was receiving methadone maintenance therapy, was admitted to the Emergency Department with necrotic tissue involving the external genitalia.Fournier's gangrene is usually due to compromised host immunity, without a precise cause of bacterial infection; here it is linked to a loco-regional intravenous injection of cocaine. A multimodal approach, including a wide surgical debridement and a postponed skin graft, was needed. Here we report this case, with a narrative review of the literature

MULTIDISCIPLINARY STUDY OF SUBSIDENCE AND SINKHOLE OCCURRENCES IN THE ACQUE ALBULE BASIN (ROMA, ITALY)

Abstract We present the results of a combined analysis of remote sensing and geophysical‐geotechnical data carried out in the Acque Albule Basin, a sinkhole prone area located close to the city of Roma, where a wide travertine wedge is present. We carried out geophysical measurements and borehole drillings over two test areas to image the subsoil where paroxysmal surficial dynamics occur. One site is marked by subsidence occurring at least since the early 2000s, whereas the other site hosts the "La Regina" and "Colonnelle" sinkhole lakes, which discharge sulfur‐carbonated waters. The stability of these two sites threatens highway, railway, and airport facilities, and this study helps to assess the geological hazard. For example, InSAR and LiDAR data helped define wide scale subsidence over the last 20 years and previously undetected small‐scale morphologies. Geophysical measurements of the latter revealed shallow and deep dissolution affecting the travertine and driving surficial paroxysmal events. Both study sites were found to lie inside a large depression located at the junction between Jurassic carbonate and Plio‐Pleistocene units in association with paleo karst morphologies in the travertine deposits and affected by the present‐past spillage of sulfurous waters. Given these elements, multidisciplinary geophysical observations are crucial for assessing and mitigating the geological risk and guiding land use planning and management