Modelo de corriente de fuga en estructuras de unión p-n fabricados a base de nitruros del grupo III en fase cubica

Mediante mediciones de SIMS, encontramos evidencia de difusión de impurezas residuales hacia el bulto de películas de GaN cubico no intencionalmente dopadas. El análisis de imágenes de espectroscopía de masas de iones secundarios (SIMS) revela que la difusión es propiciada por las fallas de apilamiento. La profundidad a la que las impurezas residuales difunden, concuerda con la distancia a la que la densidad de fallas de apilamiento alcanza su valor mínimo. Mediciones de microscopía electrónica en transmisión (TEM) muestran una alta densidad de fallas de apilamiento en las zonas de contacto ohmico de diodos de unión p-n fabricados con GaN cúbico. De acuerdo con datos reportados en la literatura que indican conducción parásita a través de defectos estructurales y con base en estos resultados, se propone un modelo de corriente de fuga en diodos de unión p-n de GaN cúbico que degradan su desempeño y/o provocan su falla

Density separation of petrous bone powders for optimized ancient DNA yields

Density separation is a process routinely used to segregate minerals, organic matter, and even microplastics, from soils and sediments. Here we apply density separation to archaeological bone powders before DNA extraction to increase endoge-nous DNA recovery relative to a standard control extraction of the same powders. Using nontoxic heavy liquid solutions, we separated powders from the petrous bones of 10 individuals of similar archaeological preservation into eight density inter-vals (2.15 to 2.45 g/cm3 , in 0.05 increments). We found that the 2.30 to 2.35 g/cm 3 and 2.35 to 2.40 g/cm3 intervals yield-ed up to 5.28-fold more endogenous unique DNA than the corresponding standard extraction (and up to 8.53-fold before duplicate read removal), while maintaining signals of ancient DNA authenticity and not reducing library complexity. Although small 0.05 g/cm 3 intervals may maximally optimize yields, a single separation to remove materials with a density above 2.40 g/cm3 yielded up to 2.57-fold more endogenous DNA on average, which enables the simultaneous separation of samples that vary in preservation or in the type of material analyzed. While requiring no new ancient DNA laboratory equipment and fewer than 30 min of extra laboratory work, the implementation of density separation before DNA extraction can substantially boost endogenous DNA yields without decreasing library complexity. Although subsequent studies are required, we present theoretical and practical foundations that may prove useful when applied to other ancient DNA substrates such as teeth, other bones, and sediments

Very late bioresorbable scaffold thrombosis and reoccurrence of dissection two years later chronic total occlusion recanalization of the left anterior descending artery

We describe the case of a patient presenting with ST-segment elevation myocardial infarction due to very late scaffold thrombosis. The patient was already admitted for an elective percutaneous recanalization of a chronically occluded left anterior descending artery (LAD). The procedure was performed according the sub-intimal tracking and re-entry (STAR) technique with 4 bioresorbable vascular scaffolds implantation. However, even though the coronary flow was preserved at the end of the procedure, the dissected segment was only partially sealed at the distal segment of the LAD. After 18 mo of regular assumption, dual antiplatelet therapy was discontinued for 10 mo before his presentation at the emergency room. This is the first reported case of a very late scaffold thrombosis after coronary chronic total occlusion (CTO) recanalization performed according to the STAR technique. This case raises concerns about the risk of very late scaffold thrombosis after complex CTO revascularization

Road traffic injuries in one local health unit in the Lazio region: results of a surveillance system integrating police and health data

<p>Abstract</p> <p>Objective</p> <p>Different sources are available for the surveillance of Road Traffic injuries (RTI), but studied individually they present several limits. In this paper we present the results of a surveillance integrating healthcare data with the data gathered by the municipal police in the southeastern area of Rome (630,000 inhabitants) during the year 2003.</p> <p>Methods</p> <p>The Municipal police RTI reports, which list the exact location, circumstances and some risk factor of the crash, were searched in the emergency visit, hospitalization and mortality databases, to integrate them with the information on health consequences.</p> <p>A multivariate analysis was conducted to evaluate risk factors (crash circumstances, age ad gender of the casualty) associated with hospital admission following a RTI.</p> <p>Mapping of RTI locations was created. The locations with higher risk of accidents with severe health consequences and at higher risk for pedestrians were identified.</p> <p>Results</p> <p>According to police records 4571 RTI occurred in 2003, 75% of which led to emergency department admissions. Sixteen percent of these emergency visits ended in hospitalization, and 44 deaths were reported within 30 days of the event, most of which occurred in young men.</p> <p>The people with the highest risk of hospitalization after an RTI were the cyclists, pedestrians and followed by people on two-wheeled vehicles. The type of crash with the highest risk of hospitalization was head-on collision.</p> <p>Geographical analyses showed four clusters with higher severity of RTI. Specific attention was paid to pedestrian injuries. Analyzing the locations of RTIs involving pedestrians permitted us to rank the most dangerous streets. The roads at high risk for pedestrians identified problems in the bus stop constructions and in the placement of the zebra pedestrian crossings.</p> <p>Conclusion</p> <p>This study proves the feasibility of an integrated surveillance system of RTI by using routinely collected local data. The high-risk locations identified with the geographic analyses method in this study highlighted infrastructural problems, suggesting immediate preventive interventions.</p

correlation between endocrinological parameters and acne severity in adult women

Many studies demonstrate increased androgen levels and high prevalence of polycystic ovaries in women affected by acne. We evaluated the relationship between clinical features, ultrasonographic data on polycystic ovaries and hormonal parameters in 129 women w17 years of age with acne. Serum levels of androgens of ovarian and adrenal origin were measured. Menstrual cycle regularity, hirsutism, body mass index and ultrasonographic evaluation of ovaries were recorded. Raised levels of at least one androgen were evident in a majority of our patients. Only 19% of them had polycystic ovary syndrome. Hirsutism and acne severity correlated negatively with serum sex hormone-binding globulin (SHBG) levels ( pv0.05). No correlation between acne severity and hirsutism was found. In post-pubertal women, severity of acne seems to depend on peripheral hyperandrogenism, with a negative relationship between the acne severity and serum SHBG levels. We strongly recommend the evaluation of serum SHBG levels in women with acne in order to select patients who can have a better response to appropriate hormonal regimes. Key words: acne; polycystic ovary; ultrasound examination; sex hormone-binding globulin; sebocyte

COVID-19 and Clinically Isolated Syndrome: Coincidence or Causative Link? A 12-Month Follow-Up Case Report

A 35-year-old female with positive anamnesis of COVID-19 infection presented with a seven-day history of headache along with tingling and numbness involving the right lower limb and visual disturbance on the right side of her vision. Magnetic resonance imaging (MRI) of the brain and C-spine were consistent with acute demyelinating lesions. However, the MAGNIMS criteria for a multiple sclerosis diagnosis were not met, and, subsequently, a diagnosis of clinically isolated syndrome (CIS) was made. At 12 months, the patient showed new inflammatory lesions in the right frontal lobe and at the septocallosal interface, a lesion of the right hemi-cord at C3, and subsequent development of vertigo and unsteadiness and signs consistent with a brainstem/cerebellar relapse. On the basis of clinical and radiological criteria in the 2017 McDonald criteria, a diagnosis of relapsing remitting multiple sclerosis was made.</jats:p

IL TRATTAMENTO DELLE DISLIPIDEMIE NELLA PREVENZIONE PRIMARIA DELLE MALATTIE CARDIOVASCOLARI: LE INDICAZIONI PER LA PRATICA CLINICA

Le dislipidemie rappresentano uno dei più importanti fattori causali della arteriosclerosi e delle sue complicanze d’organo, come l’infarto del miocardico, l’ictus e la vasculopatia periferica. Il loro appropriato trattamento rappresenta la base degli interventi di prevenzione primaria delle malattie cardiovascolari su base ischemica. In generale, per dislipidemia si intende una condizione clinica nella quale sono presenti alterazioni qualitative e/o quantitative dei lipidi e delle lipoproteine plasmatiche

Tissue coverage of a hydrophilic polymer-coated zotarolimus-eluting stent vs. a fluoropolymer-coated everolimus-eluting stent at 13-month follow-up: an optical coherence tomography substudy from the RESOLUTE All Comers trial

Aims To compare the tissue coverage of a hydrophilic polymer-coated zotarolimus-eluting stent (ZES) vs. a fluoropolymer-coated everolimus-eluting stent (EES) at 13 months, using optical coherence tomography (OCT) in an ‘all-comers' population of patients, in order to clarify the mechanism of eventual differences in the biocompatibility and thrombogenicity of the devices. Methods and results Patients randomized to angiographic follow-up in the RESOLUTE All Comers trial (NCT00617084) at pre-specified OCT sites underwent OCT follow-up at 13 months. Tissue coverage and apposition were assessed strut by strut, and the results in both treatment groups were compared using multilevel logistic or linear regression, as appropriate, with clustering at three different levels: patient, lesion, and stent. Fifty-eight patients (30 ZES and 28 EES), 72 lesions, 107 stents, and 23 197 struts were analysed. Eight hundred and eighty-seven and 654 uncovered struts (7.4 and 5.8%, P= 0.378), and 216 and 161 malapposed struts (1.8 and 1.4%, P= 0.569) were found in the ZES and EES groups, respectively. The mean thickness of coverage was 116 ± 99 µm in ZES and 142 ± 113 µm in EES (P= 0.466). No differences in per cent neointimal volume obstruction (12.5 ± 7.9 vs. 15.0 ± 10.7%) or other areas-volumetric parameters were found between ZES and EES, respectively. Conclusion No significant differences in tissue coverage, malapposition, or lumen/stent areas and volumes were detected by OCT between the hydrophilic polymer-coated ZES and the fluoropolymer-coated EES at 13-month follow-u

Potentialities of Usrp-Based Software Defined Radar Systems

International audienceSoftware Defined Radar is the latest trend in radar development. To handle enhanced radar signal processing techniques, advanced radars need to be able of generating various types of waveforms, such as frequency modulated or phase coded, and to perform multiple functions. The adoption of a Software Defined Radio system makes easier all these abilities. In this work, the implementation of a Software Defined Radar system for target tracking using the Universal Software Radio Peripheral platform is discussed. For the first time, an experimental characterization in terms of radar application is performed on the latest Universal Software Radio Peripheral NI2920, demonstrating a strongly improved target resolution with respect to the first generation platform

PET criteria by cancer type from imaging interpretation to treatment response assessment: beyond FDG PET score

Background: in recent years, the role of positron emission tomography (PET) and PET/computed tomography (PET/CT) has emerged as a reliable diagnostic tool in a wide variety of pathological conditions. This review aims to collect and review PET criteria developed for interpretation and treatment response assessment in cases of non-[18F]fluorodeoxyglucose ([18F]FDG) imaging in oncology. Methods: A wide literature search of the PubMed/MEDLINE, Scopus and Google Scholar databases was made to find relevant published articles about non-[18F]FDG PET response criteria. Results: The comprehensive computer literature search revealed 183 articles. On reviewing the titles and abstracts, 149 articles were excluded because the reported data were not within the field of interest. Finally, 34 articles were selected and retrieved in full-text versions. Conclusions: available criteria are a promising tool for the interpretation of non-FDG PET scans, but also to assess the response to therapy and therefore to predict the prognosis. However, oriented clinical trials are needed to clearly evaluate their impact on patient management