Search results for " shadow"
showing 10 items of 27 documents
Optimum Design and Performance of an Electron Gun for a Ka-Band TWT
2019
This paper deals with optimum design and development of a thermionic electron gun to meet specified beam requirements within defined electric and geometric constraints for a Ka -band traveling wave tube (TWT) for space applications. The electron gun design is based on the Pierce method and carried out according to the iterative process indicated by Vaughan. The design of a periodic permanent magnet (PPM) beam focusing system for the stability of the beam is also required. A sensitivity analysis, by varying electric parameters and geometric parameters, is presented and taken into account as a fundamental role to the aim of optimizing the design of the Pierce gun. A cathode current value of 5…
Ecological services performed by the bonobo (Pan paniscus): seed dispersal effectiveness in tropical forest.
2013
Abstract:Survival of Afrotropical primary forests depends not only on habitat protection but also on the protection of animal species such as frugivorous primates, recognized as the most important seed dispersers for many plants. Here we investigate seed-dispersal services by the bonobo (Pan paniscus) in an evergreen lowland tropical rain forest of the Congo Basin. In the long-term research site of LuiKotale, we investigated food habits and seed processing based on 22 mo of behavioural observation, seed trial experiment and long-term daily GPS tracking of a habituated ape community. Bonobos were mainly frugivores (66% of all feeding sessions), spending about 3.5 h d−1swallowing seeds that w…
The working partner in family enterprise : European and national issues
2021
The essay focuses on the discipline of the work done by one partner in the company of the other in cross-border couples and on the problems involved in this case. More specifically the focus is on the hermeneutical problems that arise both at the level of European legislation and at the level of Italian national discipline which is applicable according to European conflict criteria, showing the ambiguities and wide areas of shadow left uncovered by the latter.
Two Distinct Auditory-Motor Circuits for Monitoring Speech Production as Revealed by Content-Specific Suppression of Auditory Cortex
2015
Speech production, both overt and covert, down-regulates the activation of auditory cortex. This is thought to be due to forward prediction of the sensory consequences of speech, contributing to a feedback control mechanism for speech production. Critically, however, these regulatory effects should be specific to speech content to enable accurate speech monitoring. To determine the extent to which such forward prediction is content-specific, we recorded the brain's neuromagnetic responses to heard multisyllabic pseudowords during covert rehearsal in working memory, contrasted with a control task. The cortical auditory processing of target syllables was significantly suppressed during rehear…
Imaging findings of primary breast sarcoma : results of a first multicenter study
2016
Abstract Purpose To investigate imaging findings in patients with primary breast sarcoma (PBS). Materials and methods A retrospective search in the databases of 10 radiological departments in Germany from 2000 to 2011 was performed. Only histologically proven cases of PBS were included into the study. Mammography was available in 31 patients (33 lesions), ultrasound images in 24 patients (24 lesions), and for 10 patients (14 lesions) magnetic resonance imaging (MRI) of the breast was performed. The breast findings were classified according to the American College of Radiology Breast Imaging Reporting and Data Systems (BI-RADS) 5th edition categories. Collected data were evaluated by means o…
The size of juxtaluminal hypoechoic area in ultrasound images of asymptomatic carotid plaques predicts the occurrence of stroke
2013
Abstract OBJECTIVE: To test the hypothesis that the size of a juxtaluminal black (hypoechoic) area (JBA) in ultrasound images of asymptomatic carotid artery plaques predicts future ipsilateral ischemic stroke. METHODS: A JBA was defined as an area of pixels with a grayscale value 10 mm(2) (P 8 mm(2)) was still significant after adjusting for other plaque features known to be associated with increased risk, including stenosis, grayscale median, presence of discrete white areas without acoustic shadowing indicating neovascularization, plaque area, and history of contralateral TIA or stroke. Plaque area and grayscale median were not significant. Using the significant variables (stenosis, discr…
How personal resources predict work engagement and self-rated performance among construction workers: A social cognitive perspective
2014
Traditionally, research focussing on psychosocial factors in the construction industry has focused mainly on the negative aspects of health and on results such as occupational accidents. This study, however, focuses on the specific relationships among the different positive psychosocial factors shared by construction workers that could be responsible for occupational well-being and outcomes such as performance. The main objective of this study was to test whether personal resources predict self-rated job performance through job resources and work engagement. Following the predictions of Bandura's Social Cognitive Theory and the motivational process of the Job Demands-Resources Model, we exp…
Architettura in alzato. Questioni di territorio, paesaggio, ambiente
2021
Negata alla tipologia l’architettura del Sud nel saggio riconosce una specifica identità e perfetta eccezionalità nell’essenza del luogo. Se la facciata istituisce un rapporto con l’estetica del paesaggio, i temi che essa sottende definiscono altre significative relazioni. L’ordinamento logico delle membrature, la chiarezza geometrica e il rigore dei rapporti rimandano ad una architettura che si misura, ed è misura stessa, del territorio e della sua morfologia. A sua volta, lo spessore della facciata esprime la relazione con l’ambiente e interpreta in maniera poetica i condizionamenti climatici, intervenendo sul controllo della luce, sui vuoti nei paramenti murari, sulla determinazione dell…
Laser-Generated Acoustic Signal Interaction with Surface Flaws on Rail Wheels
2005
Long- and short-range acoustic-signal interaction with surface-breaking cracks and geometric boundaries of the rail-wheel tread area are presented in this article. Ultrasonic signals are generated using a laser-line source of varying length and distance from a crack and are detected with a 1-MHz contact transducer to map the sound field behind the crack in the near, intermediate, and far fields of the insonified region. The factors that affect the behavior of a laser-generated surface acoustic wave propagating along the tread area of a rail wheel are discussed. A signal normalization method is proposed to help in sensing the presence of a crack from the transmitted signal unaffected by the …
Sul settantesimo anniversario della Convenzione europea: fra successi e prospettive di alterazione del sistema
2020
In this paper it is submitted that an assessment of the functioning of the European system of protection of human rights lead to different results, depending on whether one considers the entire life of this system or the last twenty years (par. 1). Such an assessment is beyond any doubt positive in the first case, insofar as both the action of the States parties (progressive "jurisdictionalisation" of the protection system; extension to eastern Europe, ecc.) and the case law of the European Court (evolutive interpretation, ecc.) are concerned (par. 2). Different considerations are developed with regard to the last twenty years, despite the stipulation of Protocol 14, 15 and 16, and despite …