792 research outputs found

    Sobre um novo Nicoletiidae (Zygentoma: Insecta) do Brasil vivendo com formigas lava-pés (Hymenoptera: Formicidae)

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    A new myrmecophilous silverfish (Zygentoma: Nicoletiidae: Subnicoletiinae) from Rio de Janeiro, Brazil, found living in fire ant (Solenopsis saevissima, Formicidae: Myrmicinae) nests is described: Allotrichotriura saevissima gen. nov. sp. nov. is compared with the other genera and subgenera known in the subfamily. The main diagnostic features would include the combination of body shape, body and head setation, morphology of praetarsus, and number of abdominal stylets and vesicles. Although further quests were attempted at the type-locality, only the original described material, exclusively composed of females, remains known.Descreve-se um novo Zygentoma (Nicoletiidae: Subnicoletiinae), mirmecĂłfilo da formiga lava-pĂ©s Solenopsis saevissima (Formicidae: Myrmicinae) no Estado do Rio de Janeiro, Brasil: Allotrichotriura saevissima gen. nov. sp. nov. que Ă© comparado com os gĂ©neros e subgĂ©neros conhecidos na subfamĂ­lia. As principais caracterĂ­sticas diagnĂłsticas respeitam a combinação da forma do corpo, quetotaxia cefĂĄlica e do corpo, morfologia do prĂ©tarso e nĂșmero de estilos e vesĂ­culas abdominais. Embora prospecçÔes recentes tenham sido levadas a cabo na localidade tĂ­pica, apenas se conhece a amostra original, que integra exclusivamente fĂȘmeas

    Infratentorial hygroma secondary to decompressive craniectomy after cerebellar infarction

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    We present a case of expansive CSF collection in the cerebellar convexity. The patient was a 74 years old lady who one month before had suffered a cerebellar infarct complicated with acute hydrocephalus. She had good evolution after decompressive craniectomy without shunting. Fifteen days after surgery, the patient started with new positional vertigo, nausea and vomiting and a wound CSF fistula that needed ventriculoperitoneal shunt (medium pressure) because conservative treatment failed. After shunting, the fistula closed, but the patient symptoms worsened. The MRI showed normal ventricular size with a cerebellar hygroma, extending to the posterior interhemispheric fissure. The collection had no blood signal and expanded during observation. A catheter was implanted in the collection and connected to the shunt. The patient became asymptomatic after surgery, and the hygromas had disappeared in control CT at one month. This case shows an infrequent problem of CSF circulation at posterior fossa that resulted in vertigo of central origin. A higroma-ventricle-peritoneal shunt solved the symptoms of the patient

    Surgery guided by 5-aminolevulinic fluorescence in glioblastoma: volumetric analysis of extent of resection in singlecenter experience

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    We analyzed the efficacy and applicability of surgery guided by 5-aminolevulinic acid (ALA) fluorescence in consecutive patients with glioblastoma multiforme (GBM). Thirty-six patients with GBM were operated on using ALA fluorescence. Resections were performed using the fluorescent light to assess the right plane of dissection. In each case, biopsies with different fluorescent quality were taken from the tumor center, from the edges, and from the surrounding tissue. These samples were analyzed separately with hematoxylin-eosin examination and immunostaining against Ki67. Tumor volume was quantified with pre- and postoperative volumetric magnetic resonance imaging. Strong fluorescence identified solid tumor with 100% positive predictive value. Invaded tissue beyond the solid tumor mass was identified by vague fluorescence with 97% positive predictive value and 66% negative predictive value, measured against hematoxylin-eosin examination. All the contrast-enhancing volume was resected in 83.3% of the patients, all patients had resection over 98% of the volume and mean volume resected was 99.8%. One month after surgery there was no mortality, and new or increased neurological morbidity was 8.2%. The fluorescence induced by 5-aminolevulinic can help to achieve near total resection of enhancing tumor volume in most surgical cases of GBM. It is possible during surgery to obtain separate samples of the infiltrating cells from the tumor borde

    Identification of Cognitive Workload during Surgical Tasks with Multimodal Deep Learning

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    The operating room (OR) is a dynamic and complex environment consisting of a multidisciplinary team working together in a high take environment to provide safe and efficient patient care. Additionally, surgeons are frequently exposed to multiple psycho-organisational stressors that may cause negative repercussions on their immediate technical performance and long-term health. Many factors can therefore contribute to increasing the Cognitive Workload (CWL) such as temporal pressures, unfamiliar anatomy or distractions in the OR. In this paper, a cascade of two machine learning approaches is suggested for the multimodal recognition of CWL in four different surgical task conditions. Firstly, a model based on the concept of transfer learning is used to identify if a surgeon is experiencing any CWL. Secondly, a Convolutional Neural Network (CNN) uses this information to identify different degrees of CWL associated to each surgical task. The suggested multimodal approach considers adjacent signals from electroencephalogram (EEG), functional near-infrared spectroscopy (fNIRS) and eye pupil diameter. The concatenation of signals allows complex correlations in terms of time (temporal) and channel location (spatial). Data collection was performed by a Multi-sensing AI Environment for Surgical Task & Role Optimisation platform (MAESTRO) developed at the Hamlyn Centre, Imperial College London. To compare the performance of the proposed methodology, a number of state-of-art machine learning techniques have been implemented. The tests show that the proposed model has a precision of 93%

    Anisotropic Resistivity Surfaces Produced in ITO Films by Laser‐Induced Nanoscale Self‐organization

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    Highly anisotropic resistivity surfaces are produced in indium tin oxide (ITO) films by nanoscale self‐organization upon irradiation with a fs‐laser beam operating at 1030 nm. Anisotropy is caused by the formation of laser‐induced periodic surface structures (LIPSS) extended over cm‐sized regions. Two types of optimized structures are observed. At high fluence, nearly complete ablation at the valleys of the LIPSS and strong ablation at their ridges lead to an insulating structure in the direction transverse to the LIPSS and conductive in the longitudinal one. A strong diminution of In content in the remaining material is then observed, leading to a longitudinal resistivity ρL ≈ 1.0 Ω·cm. At a lower fluence, the material at the LIPSS ridges remains essentially unmodified while partial ablation is observed at the valleys. The structures show a longitudinal conductivity two times higher than the transverse one, and a resistivity similar to that of the pristine ITO film (ρ ≈ 5 × 10−4 Ω·cm). A thorough characterization of these transparent structures is presented and discussed. The compositional changes induced as laser pulses accumulate, condition the LIPSS evolution and thus the result of the structuring process. Strategies to further improve the achieved anisotropic resistivity results are also provided.This research was funded by the Spanish Ministry of Science, Innovation and Universities, the Spanish Research Agency (AEI, Ministry of Research and Innovation), and the European Regional Development Fund (ERDF) (grant numbers TEC2017-82464-R, PID2019-109603RA-I00, and PID2019-110430GB-C21), the “ConsejerĂ­a de EconomĂ­a y Conocimiento de la Junta de AndalucĂ­a” (PAIDI-2020 projects P18-RT-3480 and -6079). The authors also acknowledge the Consejo Superior de Investigaciones CientĂ­ficas for the “Intramural Project” (201850E057). C.L.-S. acknowledges the funding of the University of Seville through the “VI Plan Propio de InvestigaciĂłn y Transferencia de la US” (VI PPIT-US). M.M.-M. acknowledges the postdoctoral Juan de la Cierva IncorporaciĂłn grant (IJCI-2017-33317)) of the same ministry. C.F. thanks the support from the European Commission through the Marie Curie Global Fellowship grant number 844977. V.L.-F. thanks the support from European Commission/Junta de AndalucĂ­a Talent-Hub Program

    Effects of beta-alanine supplementation on brain homocarnosine/carnosine signal and cognitive function: an exploratory study

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    Objectives: Two independent studies were conducted to examine the effects of 28 d of beta-alanine supplementation at 6.4 g d-1 on brain homocarnosine/carnosine signal in omnivores and vegetarians (Study 1) and on cognitive function before and after exercise in trained cyclists (Study 2). Methods: In Study 1, seven healthy vegetarians (3 women and 4 men) and seven age- and sex-matched omnivores undertook a brain 1H-MRS exam at baseline and after beta-alanine supplementation. In study 2, nineteen trained male cyclists completed four 20-Km cycling time trials (two pre supplementation and two post supplementation), with a battery of cognitive function tests (Stroop test, Sternberg paradigm, Rapid Visual Information Processing task) being performed before and after exercise on each occasion. Results: In Study 1, there were no within-group effects of beta-alanine supplementation on brain homocarnosine/carnosine signal in either vegetarians (p = 0.99) or omnivores (p = 0.27); nor was there any effect when data from both groups were pooled (p = 0.19). Similarly, there was no group by time interaction for brain homocarnosine/carnosine signal (p = 0.27). In study 2, exercise improved cognitive function across all tests (P0.05) of beta-alanine supplementation on response times or accuracy for the Stroop test, Sternberg paradigm or RVIP task at rest or after exercise. Conclusion: 28 d of beta-alanine supplementation at 6.4g d-1 appeared not to influence brain homocarnosine/ carnosine signal in either omnivores or vegetarians; nor did it influence cognitive function before or after exercise in trained cyclists

    PrĂĄcticas de laboratorio de fisicoquĂ­mica de los materiales. -- 3a. ediciĂłn, 2007.

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    89 påginas.Contiene 9 pråcticas de laboratorio: 1. Volumen molar parcial. -- 2. Procesos con gas ideal. -- 3. Equilibrio líquido-vapor. -- 4. Equilibrio sólido-líquido. -- 5. Equilibrio químico en reacciones homogéneas. -- 6. Constante de disociación. -- 7. Solubilidad. -- 8. Equilibrio metal-ión metålico. -- 9. Cinética química. Al inicio del texto incluye medidas preventivas y correctivas como normas de seguridad

    PrĂĄcticas de laboratorio de fisicoquĂ­mica de los materiales. -- 2a. ediciĂłn, 2000.

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    1 archivo PDF (x, 63 påginas) 2a ed. 2000, 2a reimpresión 2006.Contiene 9 pråcticas de laboratorio: 1. Volumen molar parcial. -- 2. Procesos con gas ideal. -- 3. Equilibrio líquido-vapor. -- 4. Equilibrio sólido-líquido. -- 5. Equilibrio químico en reacciones homogéneas. -- 6. Constante de disociación. -- 7. Solubilidad. -- 8. Equilibrio metal-ión metålico. -- 9. Cinética química. Al inicio del texto incluye medidas preventivas y correctivas como normas de seguridad

    Hypofractionated radiation therapy and temozolomide in patients with glioblastoma and poor prognostic factors. A prospective, single-institution experience

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    Background: Hypofractionated radiation therapy is a feasible and safe treatment option in elderly and frail patients with glioblastoma. The aim of this study was to evaluate the effectiveness of hypofractionated radiation therapy with concurrent temozolomide in terms of feasibility and disease control in primary glioblastoma patients with poor prognostic factors other than advanced age, such as post-surgical neurological complications, high tumor burden, unresectable or multifocal lesions, and potential low treatment compliance due to social factors or rapidly progressive disease. Material and methods: GTV included the surgical cavity plus disease visible in T1WI-MRI, FLAIR-MRI and in the MET-uptake. The CTV was defined as the GTV plus 1.5-2 cm margin; the PTV was the CTV+0.3 cm margin. Forty, fourty-five, and fifty grays in 15 fractions were prescribed to 95% of PTV, CTV, and GTV, respectively. Treatment was delivered using IMRT or the VMAT technique. Simultaneously, 75 mg/m2/day of temozolomide were administered. Results: Between January 2010 and November 2017, we treated a total of 17 patients. The median age at diagnosis was 68-years; median KPS was 50-70%. MGMT-methylation status was negative in 5 patients, and 8 patients were IDH-wildtype. Eight of 18 patients were younger than 65-years. Median tumor volume was 26.95cc; median PTV volume was 322cc. Four lesions were unresectable; 6 patients underwent complete surgical resection. Median residual volume was 1.14cc. Progression-free survival was 60% at 6 months, 33% at 1-year and 13% at 2-years (median OS = 7 months). No acute grade 3-5 toxicities were documented. Symptomatic grade 3 radiation necrosis was observed in one patient. Conclusions: Patients with poor clinical factors other than advanced age can be selected for hypofractionated radiotherapy. The OS and PFS rates obtained in our series are similar to those in patients treated with standard fractionation, assuring good treatment adherence, low rates of toxicity and probable improved cost-effectiveness
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