6,987 research outputs found
Energy-sharing asymmetries in ionization by positron impact
The triply differential cross section of molecular hydrogen for ionization by 50 eV positrons has been determined, for the first time, for both the ejected electron in coincidence with the remnant ion and for the scattered projectile. Asymmetries in the energy sharing between the two light particles in the final state are observed, with the electron spectrum being shifted to significantly lower (and the scattered positron to correspondingly higher) energies than expected. A similar shape is observed in the case of the ejected electron spectrum from a helium target at the same excess energy
Thermal Insulation of a Flour Mill to Improve Effectiveness of the Heat Treatment for Insect Pest Control
One of the major problems that are found in flour mills, and more generally in industries for the processing and storage of food, concerns the control of insect pests. Insects can develop and are responsible for contamination that can determine the non-conformity of productions to the norms and regulations. An alternative to chemical treatments for the control of insect pests in flour mills is given by methods based on heat treatment of indoor environment. The heat treatment consists in raising the temperature of the surfaces where the insects live by increasing the air temperature inside the building. The optimum air temperature for the effectiveness of the heat treatment ranges between 47 °C and 55 °C and must be maintained for a period of 36÷48 hours to eliminate all life stages of insect pests both for dehydration and for irreversible alterations in lipid and protein levels. The most widely used system for heat treatment in flour mills is based on heaters powered by electricity which are usually integrated with fans to ensure a uniform air temperature inside the buildings. The objective of this research was to analyse the heat transfer of a number of building elements belonging to a flour mill located in Eastern Sicily (Italy) in order to highlight the weakness of the building thermal behaviour. Firstly, building materials and components, such as floors, external walls, windows, pillars and beams, were analysed. Next, thermal characteristics of the indoor environment were studied before and during the heat treatment. Specifically, air temperature and relative humidity inside and outside the building were measured by means of data-loggers; surface temperatures of the building components were measured by using a thermal camera; thermal conductivities of the building materials were collected from materials catalogues. The monitoring of the microclimatic parameters inside and outside the building before and during the heat treatment revealed that a relevant heat loss occurred across thermal bridges which were previously identified by analysing digital images provided by the thermal camera. On the one hand, thermal bridges represented a weakness of the thermal treatment since insects found refuge in areas of the building characterized by lower surface temperatures; on the other hand they caused a huge expenditure of electrical energy in order to maintain indoor air temperature within the optimal range. Therefore, the building components which constituted the thermal bridges were analysed with the aim of studying the contributions of different insulation materials on heat loss. Simulations were carried out by using different insulation solutions to quantify heat loss reduction. A set of possible solutions was reported in this paper
Infinite impulse response modal filtering in visible adaptive optics
Diffraction limited resolution adaptive optics (AO) correction in visible
wavelengths requires a high performance control. In this paper we investigate
infinite impulse response filters that optimize the wavefront correction: we
tested these algorithms through full numerical simulations of a
single-conjugate AO system comprising an adaptive secondary mirror with 1127
actuators and a pyramid wavefront sensor (WFS). The actual practicability of
the algorithms depends on both robustness and knowledge of the real system:
errors in the system model may even worsen the performance. In particular we
checked the robustness of the algorithms in different conditions, proving that
the proposed method can reject both disturbance and calibration errors
A critical analysis of happiness and well-being. Where we stand now, where we need to go
This paper aims to critically analyse happiness and well-being to find novel ways for theorizing and promoting better life conditions for individuals and societies. The necessity to shift from a subjective view of individual well-being to a more social and contextual version of these constructs is the common thread running throughout the whole work. To this end, the first part introduces the reader into the complexity of the happiness and well-being scholarship by outlining some of the most relevant approaches developed by the psychological and economic literature. After highlighting the limitations of both disciplines, the second part of the paper presents some alternative models, namely the Feminist Economics, the Capabilities Approach, and the model of Four Qualities of Life. In addition to these, we will draw attention, in the last section, to the Critical Community Psychology approach to happiness and well-being. Our main argument is that this emerging discipline bears the potential to frame the pursuit of the good life in a whole new fashion that takes into account a) contextual features, in particular the recourses that a given environment offers and the opportunity to access them, b) the role of power, justice, and liberation, and c) the value of participation, reciprocity, and ethics of care. Current limitations of CCP are also discussed and future directions outlined
Impact of Sodium Layer variations on the performance of the E-ELT MCAO module
Multi-Conjugate Adaptive Optics systems based on sodium Laser Guide Stars may
exploit Natural Guide Stars to solve intrinsic limitations of artificial
beacons (tip-tilt indetermination and anisoplanatism) and to mitigate the
impact of the sodium layer structure and variability. The sodium layer may also
have transverse structures leading to differential effects among Laser Guide
Stars. Starting from the analysis of the input perturbations related to the
Sodium Layer variability, modeled directly on measured sodium layer profiles,
we analyze, through a simplified end-to-end simulation code, the impact of the
low/medium orders induced on global performance of the European Extremely Large
Telescope Multi-Conjugate Adaptive Optics module MAORY.Comment: 7 pages, 5 figures, SPIE conference Proceedin
Seismic Analysis of Traditional Stone Rural Buildings: Case study of a one-storey building
Specific features of traditional rural buildings can influence the assessment of their seismic behaviour. When a change in intended use of traditional rural buildings is necessary, restoration work must comply with specific seismic norms and should preserve their original features. In this paper, a model for the seismic safety verification of masonry walls for inplane actions was applied to investigate the structural behaviour of one-storey stone-masonry traditional rural buildings, in relation to standards application and possible retrofitting interventions. The results showed that pier-panel collapse mechanisms and the simulation method of masonry spandrel behaviour are of importance and affect the need to provide for strengthening interventions
From "Gomorrah Domain" to "Don Peppe Diana Lands". A Southern Italian Experience of Work-Based Liberation, Community Networking, and Well Being
The article describes working experiences in relation to empowering activities, which have been carried out in a local community in the province of Caserta (in Southern Italy), a place characterized by the widespread presence of organized criminal groups. In this study, workplace is intended as a community network aimed at the promotion of coscientization, liberation, and well-being. Specifically, this paper features initiatives and projects aimed at establishing new community values through a re-construction of a work-based social system standing against criminal clans, which tend to dominate not only economical transactions but also civil life
Common features between neoplastic and preneoplastic lesions of the biliary tract and the pancreas
The bile duct system and pancreas show many similarities due to their anatomical proximity and common embryological origin. Consequently, preneoplastic and neoplastic lesions of the bile duct and pancreas share analogies in terms of
molecular, histological and pathophysiological features. Intraepithelial neoplasms are reported in biliary tract, as biliary intraepithelial neoplasm (BilIN), and in pancreas, as pancreatic intraepithelial neoplasm (PanIN). Both can evolve
to invasive carcinomas, respectively cholangiocarcinoma (CCA) and pancreatic ductal adenocarcinoma (PDAC). Intraductal papillary neoplasms arise in biliary tract and pancreas. Intraductal papillary neoplasm of the biliary tract (IPNB)
share common histologic and phenotypic features such as pancreatobiliary, gastric, intestinal and oncocytic types, and biological behavior with the pancreatic counterpart, the intraductal papillary mucinous neoplasm of the pancreas (IPMN). All these neoplastic lesions exhibit similar immunohistochemical phenotypes, suggesting a common carcinogenic process.
Indeed, CCA and PDAC display similar clinic-pathological features as growth pattern, poor response to conventional chemotherapy and radiotherapy and, as a consequence, an unfavorable prognosis. The objective of this review is to discuss similarities and differences between the neoplastic lesions of the pancreas and biliary tract with potential implications on a common origin from similar stem/progenitor cells
Culture and Community Interactions: Essentials for understanding in a globalised world
"Introduction to the issue
End to end numerical simulations of the MAORY multiconjugate adaptive optics system
MAORY is the adaptive optics module of the E-ELT that will feed the MICADO
imaging camera through a gravity invariant exit port. MAORY has been foreseen
to implement MCAO correction through three high order deformable mirrors driven
by the reference signals of six Laser Guide Stars (LGSs) feeding as many
Shack-Hartmann Wavefront Sensors. A three Natural Guide Stars (NGSs) system
will provide the low order correction. We develop a code for the end-to-end
simulation of the MAORY adaptive optics (AO) system in order to obtain
high-delity modeling of the system performance. It is based on the IDL language
and makes extensively uses of the GPUs. Here we present the architecture of the
simulation tool and its achieved and expected performance.Comment: 8 pages, 4 figures, presented at SPIE Astronomical Telescopes +
Instrumentation 2014 in Montr\'eal, Quebec, Canada, with number 9148-25
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