532 research outputs found
Airborne acoustic emission of an abrasive waterjet cutting system as means for monitoring the jet cutting capability
Abrasive waterjet cutting is a manufacturing technology making use of a high-speed waterjet with abrasive particles in suspension, for cutting materials with different mechanical properties. Product quality requirements are pushing towards an improvement of tracking and stabilization methods of the relevant process variables. Amongst those, the jet kinetic power defines the cutting capability and has a significant impact on the final cut features. This variable is subject to relevant fluctuations versus time. Besides, the current state of the art does not provide means for its in-line monitoring. The aim of this contribution is to monitor the airborne acoustic emission of an abrasive waterjet cutting head and investigate its correlation with the jet kinetic power. The investigation is carried out by means of factorial studies, in which the jet is fired at various water pressures and abrasive feed rates, providing different kinetic powers. The acoustic emission is synchronously monitored by means of a condenser microphone, installed on the cutting head. Data at frequencies above 40 kHz is found to constitute a robust and selective acoustic signature of the airborne jet. The acoustic signature is proven to be an effective in-line indicator of the jet kinetic power and its pressure-induced variations, whilst abrasive-induced variations remain undetected. A calibration procedure is presented, for translating the acoustic data into a jet kinetic power. The method is validated by means of further experiments that envisage its deployment in a real scenario. Overall, the presented method constitutes a robust tool for monitoring pressure-induced variations of the jet cutting capability
Applicability of abrasive waterjet cutting to irradiated graphite decommissioning
Characterization, dismantling and pre-disposal management of irradiated graphite (i-graphite) have an important role in safe decommissioning of several nuclear facilities which used this material as moderator and reflector. In addition to common radiation protection issues, easily volatizing long-lived radionuclides and stored Wigner energy could be released during imprudent retrieval and processing of i-graphite. With this regard, among all cutting technologies, abrasive waterjet (AWJ) can successfully achieve all of the thermo-mechanical and radiation protection objectives. In this work, factorial experiments were designed and systematically conducted to characterize the AWJ processing parameters and the machining capability. Moreover, the limitation of dust production and secondary waste generation has been addressed since they are important aspects for radiation protection and radioactive waste management. The promising results obtained on non-irradiated nuclear graphite blocks demonstrate the applicability of AWJ as a valid technology for optimizing the retrieval, storage, and disposal of such radioactive waste. These activities would benefit from the points of view of safety, management, and costs
Successful neuropsychological rehabilitation in a patient with Cerebellar Cognitive Affective Syndrome
The objective of this case study was to describe the neuropsychological rehabilitation of a 16-year-old patient who presented a Cerebellar Cognitive Affective Syndrome (CCAS) following a bilateral cerebellar hemorrhage. The patient presented severe and diffuse cognitive deficits, massive behavioral disorders, and emotion regulation difficulties. The cognitive rehabilitation was performed in the chronic phase (one year after the onset of the hemorrhage) using a transdisciplinary neurobehavioral approach based on the patient's favorite interest (soccer). A significant behavioral and cognitive improvement was observed. The patient became progressively independent in all activities of daily living and was discharged home. The Functional Independence Measure at discharge was 124/126 (vs. 37/126 at entry). The patient was able to complete his schooling despite the mild cognitive and behavioral sequelae. This first description of the use of neurobehavioral therapy in a case of chronic CCAS suggests that (a) major clinical improvement can occur more than one year after the onset of the CCAS, showing the importance of long-term and intensive neurorehabilitation; and (b) when the cerebellum cannot properly play its regulator role in cognition, neuropsychological intervention through a behavioral and cognitive approach can be of great help by acting as an external modulator to help the patient regain control over himself
Nego Fugido
This text investigates the popular cultural manifestation of Nego Fugido, its relations with the history of Brazil and how it affects the fishing community of Acupe, state of Bahia, where the event is being held. We present a description of the event, they’re symbolic elements, as they stand out in the character’s costumes, the processes that involve this movement movement in the narrative itself and that are mixed in the stories and legends of the residents. From experience lived in the event, records and sketches in drawing were made, during and after the presentation which split into artistc prodution that reflect the expressiveness of the event. The research generates a reflection on the concepts of identity and tradition that permeate the movement, as well as the factors of vigilance and power relations present in each represented character. Furthermore, it highlights the important role of memory in the lived experiences that become significant throughout life, serving as propelling springs for the creative process in the field of Visual Arts.Este texto investiga la manifestación cultural popular de Nego Fugido, sus relaciones con la historia de Brasil y cómo afecta a la comunidad pesquera de Acupe, estado de Bahia, donde se realiza el evento. Presentamos una descripción del evento, sus elementos simbólicos, como se destacan en el vestuario del personaje, los procesos que involucran este movimiento en la propria narrativa y que se mesclan en las historias y leyendas de los vecinos. A partir de la experiencia vivida en el evento, se realizaran registros y dibujos, durante y después de la presentación, que se dividieran en producciones artísticas que reflejan la expresividad del evento. La investigación genera una reflexión sobre los conceptos de identidad y tradición que permean el movimiento, así como los factores de vigilancia y relaciones poder presentes en cada personaje representado. Además, destaca el importante papel de la memoria en las experiencias vividas que se vuelven significativas a lo largo de la vida, sirviendo como resortes impulsores del proceso creativo en el campo de las Artes Visuales.Esse texto investiga a manifestação cultural popular do Nego Fugido, suas relações com a história do Brasil e de que maneira afeta a comunidade pesqueira de Acupe, estado da Bahia, local onde é realizado o evento. Apresentamos uma descrição do evento, seus elementos simbólicos, como se destacam nas indumentárias das personagens, os processos que envolvem esse movimento na narrativa em si e que se mesclam nos causos e relatos dos moradores. A partir da experiência vivenciada no evento, foram realizados registros e esboços em desenho, durante e após a apresentação que se desmembraram em produções artísticas que refletem a expressividade do evento. São tecidas reflexões acerca dos conceitos de identidade e tradição que permeiam o movimento, assim como os fatores de vigilância e relações de poder presentes nos personagens. Aponta o papel da memória nas experiências vivenciadas que se tornam significativas ao longo da vida, servindo de molas propulsoras para o processo criativo no campo das Artes Visuais
Lymphadenectomy improves outcome in dogs with resected Kiupel high-grade cutaneous mast cell tumours and overtly metastatic regional lymph nodes
Historically, the prognosis for dogs with stage II Kiupel high-grade cutaneous mast cell tumours has been considered poor
A new neuropsychological instrument measuring effects of age and drugs on fitness to drive: development, reliability, and validity of MedDrive
Background: Current guidelines underline the limitations of existing instruments to assess fitness to drive and the poor adaptability of batteries of neuropsychological tests in primary care settings. Aims: To provide a free, reliable, transparent computer based instrument capable of detecting effects of age or drugs on visual processing and cognitive functions. Methods: Relying on systematic reviews of neuropsychological tests and driving performances, we
conceived four new computed tasks measuring: visual processing (Task1), movement attention shift (Task2), executive response, alerting and orientation gain (Task3), and spatial memory (Task4). We then planned five studies to test MedDrive's reliability and validity. Study-1 defined instructions and learning functions collecting data from 105 senior drivers attending an automobile club course. Study-2 assessed concurrent validity for detecting minor cognitive impairment (MCI) against useful field of view (UFOV) on 120 new senior drivers. Study-3 collected data from 200 healthy drivers aged 20-90 to model age related normal cognitive decline. Study-4 measured MedDrive's reliability having 21 healthy volunteers repeat tests five times. Study-5 tested MedDrive's responsiveness to alcohol in a randomised, double-blinded, placebo, crossover, dose-response validation trial including 20 young healthy
volunteers. Results: Instructions were well understood and accepted by all senior drivers. Measures of visual processing (Task1) showed better performances than the UFOV in detecting MCI (ROC 0.770 vs. 0.620; p=0.048). MedDrive was capable of explaining 43.4% of changes occurring with natural cognitive decline. In young healthy drivers, learning effects became negligible from the third session onwards for all tasks except for dual tasking (ICC=0.769). All
measures except alerting and orientation gain were affected by blood alcohol concentrations. Finally, MedDrive was able to explain 29.3% of potential causes of swerving on the driving simulator. Discussion and conclusions: MedDrive reveals improved performances compared to existing computed neuropsychological tasks. It shows promising results both for clinical and research purposes
The Agile Alert System For Gamma-Ray Transients
In recent years, a new generation of space missions offered great
opportunities of discovery in high-energy astrophysics. In this article we
focus on the scientific operations of the Gamma-Ray Imaging Detector (GRID)
onboard the AGILE space mission. The AGILE-GRID, sensitive in the energy range
of 30 MeV-30 GeV, has detected many gamma-ray transients of galactic and
extragalactic origins. This work presents the AGILE innovative approach to fast
gamma-ray transient detection, which is a challenging task and a crucial part
of the AGILE scientific program. The goals are to describe: (1) the AGILE
Gamma-Ray Alert System, (2) a new algorithm for blind search identification of
transients within a short processing time, (3) the AGILE procedure for
gamma-ray transient alert management, and (4) the likelihood of ratio tests
that are necessary to evaluate the post-trial statistical significance of the
results. Special algorithms and an optimized sequence of tasks are necessary to
reach our goal. Data are automatically analyzed at every orbital downlink by an
alert pipeline operating on different timescales. As proper flux thresholds are
exceeded, alerts are automatically generated and sent as SMS messages to
cellular telephones, e-mails, and push notifications of an application for
smartphones and tablets. These alerts are crosschecked with the results of two
pipelines, and a manual analysis is performed. Being a small scientific-class
mission, AGILE is characterized by optimization of both scientific analysis and
ground-segment resources. The system is capable of generating alerts within two
to three hours of a data downlink, an unprecedented reaction time in gamma-ray
astrophysics.Comment: 34 pages, 9 figures, 5 table
P2393Diagnostic accuracy of coronary CT angiography performed in 100 consecutive patients with coronary stents using a novel whole-organ high-definition CT scanner
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Government institutions and the dynamics of urban growth in China
Economic growth in China in recent decades has largely rested on the dynamism of its cities. High economic growth has coincided with measures aimed at improving the efficiency of local governments and with a mounting political drive to curb corruption. Yet the connection between government institutions and urban growth in China remains poorly understood. This paper is the first to look into the link between government efficiency and corruption, on the one hand, and urban growth in China, on the other hand and to assess what is the role of institutions relative to more traditional factors for economic growth in Chinese cities. Using panel data for 283 cities over the period between 2003 and 2014, the results show that the urban growth in China is a consequence of a combination of favorable human capital, innovation, density, local conditions, foreign direct investment, and city-level government institutions. Both government quality—especially for those cities with the best governments—and the fight against corruption at the city level have a direct effect on urban growth. Measures to tackle corruption at the provincial level matter in a more indirect way, by raising or lowering the returns of other growth-inducing factors
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