3,339 research outputs found
The Impact of Performance Management System Characteristics on Perceived Effectiveness of the System and Engagement
The purpose of this study was to comprehensively examine performance management systems to determine the characteristics that are most influential in predicting desirable organizational outcomes. Results of an online survey administered to 159 participants revealed that the four performance management system categories significantly predicted employees’ perceived effectiveness of their performance management system and employee engagement. The activities category was found to be the strongest predictor of perceived effectiveness and employee engagement. Four performance management system characteristics significantly led employees to perceive their performance management system to be effective and be engaged at work. These four performance management system characteristics include systems that focused on the results employees achieved, evaluated employees on their contextual performance, facilitated the construction of individual development plans for employees, and allowed for participative decision making between managers and subordinates. The results suggested that organizations should implement these characteristics into their performance management system to increase perceived effectiveness of the system and employee engagement
Valors semà ntics i pragmà tics de l’imperfet italià : cap a un procediment interpretatiu comú
This paper proposes an account of the semantics and pragmatics of the Italian indicative imperfect. This tense is described as deriving all of its uses from an extremely reduced core of semantic features as the point of departure to a series of interpretative paths leading to different context-related possible interpretations through a process of pragmatic enrichment. With regard to the temporal parameter, the semantics of the imperfect is described as conveying past temporal reference, with an underdetermined scope. With regard to the aspectual parameter, this tense is defined as not semantically determined at all. Upon pragmatic integration of contextual information, three main classes of meaning effects associated with the imperfect are assumed to emerge: a narrative effect, an evidential effect and an effect of activation of a preliminary phase in relation to the event. Based on the above mentioned features, an overall semantic-pragmatic mapping of the imperfect and of its interpretive procedure is proposed.Aquest article dóna compte de la semà ntica i la pragmà tica de l’imperfet italià . A la nostra descripció es mostra que aquest temps verbal deriva tots els seus usos d’un nucli extremadament reduït de trets semà ntics, que són el punt de partida d’una sèrie de camins interpretatius que ens porten a diferents interpretacions possibles lligades al context mitjançant un procés d’enriquiment pragmà tic. Pel que fa al parà metre temporal, mostrem que la semà ntica de l’imperfet denota una referència temporal de passat d’abast indeterminat. Pel que fa al parà metre aspectual, aquest temps no està semà nticament definit en absolut. A partir de la integració pragmà tica de la informació contextual, apareixen tres classes principals d’efectes semà ntics associats a l’imperfet: un efecte narratiu, un efecte evidencial i un efecte d’activació d’una fase anterior a l’esdeveniment denotat. Tot basant-nos en els trets esmentats, proposem una projecció de l’imperfet i del seu procediment interpretatiu des de la semà ntica a la pragmà tica
Searching for circumplanetary disks around LkCa 15
We present Karl G. Jansky Very Large Array (VLA) observations of the 7 mm
continuum emission from the disk surrounding the young star LkCa 15. The
observations achieve an angular resolution of 70 mas and spatially resolve the
circumstellar emission on a spatial scale of 9 AU. The continuum emission
traces a dusty annulus of 45 AU in radius that is consistent with the dust
morphology observed at shorter wavelengths. The VLA observations also reveal a
compact source at the center of the disk, possibly due to thermal emission from
hot dust or ionized gas located within a few AU from the central star. No
emission is observed between the star and the dusty ring, and, in particular,
at the position of the candidate protoplanet LkCa 15 b. By comparing the
observations with theoretical models for circumplanetary disk emission, we find
that if LkCa~15~b is a massive planet (>5 M_J) accreting at a rate greater than
1.e-6 M_J yr^{-1}, then its circumplanetary disk is less massive than 0.1 M_J,
or smaller than 0.4 Hill radii. Similar constraints are derived for any
possible circumplanetary disk orbiting within 45 AU from the central star. The
mass estimate are uncertain by at least one order of magnitude due to the
uncertainties on the mass opacity. Future ALMA observations of this system
might be able to detect circumplanetary disks down to a mass of 5.e-4 M_J and
as small as 0.2 AU, providing crucial constraints on the presence of giant
planets in the act of forming around this young star.Comment: Accepted for publication on Ap
Riassetto del trasporto pubblico di Firenze a seguito dell’entrata in servizio di nuove linee di tram (Upgrading of Florence public transport to incorporate new tramlines)
Nel 2018 due nuove linee di tram entreranno in servizio a Firenze, modificando la rete del trasporto pubblico nella zona nord della cittĂ . Lo studio esamina e
confronta due soluzioni, una più innovativa e una più conservativa, progettate per migliorare il servizio di trasporto pubblico su gomma nell’area centro-settentrionale della Città Metropolitana di Firenze. Le soluzioni esaminate favoriscono l’integrazione tra le reti di autobus e tram, riducendo il flusso di traffico in aree strategiche d’interesse pubblico quali stazioni ferroviarie o settori ad alta domanda di traffico. Per ogni soluzione, l’articolo presenta lo studio della fattibilità tecnica e della relativa redditività finanziaria. Attraverso software di pianificazione e gestione del trasporto pubblico sono state valutate le caratteristiche tecniche e funzionali delle soluzioni proposte. I risultati dello studio evidenziano come la soluzione più innovativa sia quella migliore, sia dal punto di vista dell’efficienza del sistema, sia da quello economico, perché garantisce un miglioramento generale del servizio.In the last years, two new tramlines have been designed in the network of mass transit system in Florence. The planned lines will be in service in 2018 and they will serve the Northern part of the city. The work examines and compares two engineered solutions to improve the public transport service in the Northern and central areas of Florence: the former is more conservative, the latter more innovative. The alternatives facilitate the integration between the bus and tram network, reducing the traffic flow in strategical areas of public interest, such as railway stations or public offices areas. For each proposed scenario, the study consists of analysing the transport feasibility and financial viability. Specific transportation tools allowed evaluating the technical and functional characteristics of the proposed scenarios, while the economic impact is assessed using data provided by the consortium, which currently
manages the public transport in the city. The results of this study suggest the more innovative solution as the best one, from both the transportation and economic points of view, because it guarantees an overall improvement of the service
Dragon: Multidimensional Range Queries on Distributed Aggregation Trees,
Distributed query processing is of paramount importance in next-generation distribution services, such as Internet of
Things (IoT) and cyber-physical systems. Even if several multi-attribute range queries supports have been proposed for
peer-to-peer systems, these solutions must be rethought to fully meet the requirements of new computational paradigms
for IoT, like fog computing. This paper proposes dragon, an ecient support for distributed multi-dimensional range
query processing targeting ecient query resolution on highly dynamic data. In dragon nodes at the edges of the
network collect and publish multi-dimensional data. The nodes collectively manage an aggregation tree storing data
digests which are then exploited, when resolving queries, to prune the sub-trees containing few or no relevant matches.
Multi-attribute queries are managed by linearising the attribute space through space lling curves. We extensively
analysed dierent aggregation and query resolution strategies in a wide spectrum of experimental set-ups. We show that
dragon manages eciently fast changing data values. Further, we show that dragon resolves queries by contacting a
lower number of nodes when compared to a similar approach in the state of the art
AoI-based Multicast Routing over Voronoi Overlays with Minimal Overhead
The increasing pervasive and ubiquitous presence of devices at the edge of
the Internet is creating new scenarios for the emergence of novel services and
applications. This is particularly true for location- and context-aware
services. These services call for new decentralized, self-organizing
communication schemes that are able to face issues related to demanding
resource consumption constraints, while ensuring efficient locality-based
information dissemination and querying. Voronoi-based communication techniques
are among the most widely used solutions in this field. However, when used for
forwarding messages inside closed areas of the network (called Areas of
Interest, AoIs), these solutions generally require a significant overhead in
terms of redundant and/or unnecessary communications. This fact negatively
impacts both the devices' resource consumption levels, as well as the network
bandwidth usage. In order to eliminate all unnecessary communications, in this
paper we present the MABRAVO (Multicast Algorithm for Broadcast and Routing
over AoIs in Voronoi Overlays) protocol suite. MABRAVO allows to forward
information within an AoI in a Voronoi network using only local information,
reaching all the devices in the area, and using the lowest possible number of
messages, i.e., just one message for each node included in the AoI. The paper
presents the mathematical and algorithmic descriptions of MABRAVO, as well as
experimental findings of its performance, showing its ability to reduce
communication costs to the strictly minimum required.Comment: Submitted to: IEEE Access; CodeOcean: DOI:10.24433/CO.1722184.v1;
code: https://github.com/michelealbano/mabrav
Development of Fluorescence Polarization Assays for the Molecular Chaperone Hsp70 Family Members: Hsp72 and DnaK
The heat shock protein 70 (Hsp70) family of chaperones play crucial roles in protein folding and have been linked to numerous diseases. We were interested in developing a generally applicable assay format for the Hsp70 family and have developed fluorescence polarization based assays for both the mammalian Hsp72 and its bacterial counterpart, DnaK. These assays are comparable in assay set-up, incubation conditions and buffer components. Both unfolded polypeptides and synthetic peptides can be utilized as tracers to detect binding although peptides meeting the minimum seven residue length for Hsp70 binders have weaken binding when modified with fluorescein presumably due to steric effects. Although we did not identify a suitable general substrate for all Hsp70 proteins, fluorescein tagged peptide substrates that gave high affinity binding were identified for both DnaK and hsp72. We would predict that these assays will be suitable for identifying both selective chemical probes of Hsp70 family members and “pan” Hsp70 inhibitors
The National Ethics Committee: a truly valuable asset for clinical trials?
Advances in biomedicine, increased patient autonomy, and higher average life expectancy, have
contributed to raising a multitude of questions relating to Clinical Ethics. Though these aspects stand on
their own, national or community-level legislation that is unable to meet Ethical demands, or satisfies
them only partially, it will never be able to satisfy aims and interests of a rapidly changing society. The
Ethical protection of the individual in the context of life and health has been entrusted to independent,
impartial bodies: Territorial Ethics Committees. In 2015, Minacori et al1 posed the following question:
Research Ethics Committees and clinical research in Italy: where are we going? After analyzing the Italian
legislation regulating Ethics Committees and their practices, the authors noted that though the November
2012 Law had harmonized Territorial Ethical Committee activities at a national level, it neglected to address
certain critical points such as the differing deadlines by which the Committees were required to present
their opinions, and the drastic reduction of the Committees themselves which had, in fact, hampered
their activity. What’s more, problems arose from the need for Committee members to receive specific
training2 and delays in presenting opinions in research institutes extraneous to those in which the Ethical
issue had originally arisen
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