2,346 research outputs found
A blockchain-based Decentralized System for proper handling of temporary Employment contracts
Temporary work is an employment situation useful and suitable in all
occasions in which business needs to adjust more easily and quickly to workload
fluctuations or maintain staffing flexibility. Temporary workers play therefore
an important role in many companies, but this kind of activity is subject to a
special form of legal protections and many aspects and risks must be taken into
account both employers and employees. In this work we propose a
blockchain-based system that aims to ensure respect for the rights for all
actors involved in a temporary employment, in order to provide employees with
the fair and legal remuneration (including taxes) of work performances and a
protection in the case employer becomes insolvent. At the same time, our system
wants to assist the employer in processing contracts with a fully automated and
fast procedure. To resolve these problems we propose the D-ES (Decentralized
Employment System). We first model the employment relationship as a state
system. Then we describe the enabling technology that makes us able to realize
the D-ES. In facts, we propose the implementation of a DLT (Decentralized
Ledger Technology) based system, consisting in a blockchain system and of a
web-based environment. Thanks the decentralized application platforms that
makes us able to develop smart contracts, we define a discrete event control
system that works inside the blockchain. In addition, we discuss the temporary
work in agriculture as a interesting case of study.Comment: Accepted for publication in the proceedings of the "Computing
Conference 2018" - 10-12 July 2018 - London, United Kingdo
Ressenyes
Index de les obres ressenyades: MercĂš RODOREDA, Sa Pratza de su Diamant
Colonizzazione sabauda e diaspora greca, Giampaolo Salice, Sette CittĂ , Viterbo
Il lavoro di Giampaolo Salice, nelle sua densitĂ e complessitĂ , si presta a letture polisemiche partendo giĂ dallâinteressante introduzione in cui cerca di âafferrareâ il concetto sfuggente di diaspora. La riflessione sul significato di diaspora Ăš portata avanti sulla base dellâimponente ricerca bibliografica condotta dallâautore: dalle origini greche del termine, passando per le definizioni di William Safran, Robin Cohen, James Clifford e Brian Keith Axel1. Le comunitĂ diasporiche sono multi-centriche, legate piĂč o meno debolmente al luogo dâorigine (fisico o mitologico) in perenne movimento e connesse a un network. Riportando un concetto di Miguel Mellino, Salice scrive: «In un mondo digitalmente interconnesso, comprendere i fenomeni diasporici Ăš necessitĂ non solo degli scienziati sociali, ma anche delle masse di individui che sperimentano un sentimento di connessione a una vicenda collettiva di sradicamento, la quale sembra resistere allâerosione del dimenticare, dellâassimilare, dellâallontanare»2. Il tema si presta dunque a letture sia storiche sia dâattualitĂ : le complessitĂ diasporiche saranno oggetto di riflessione e discussione anche nel futuro prossimo, considerati i recenti eventi mondiali
Monitoring Lys-tRNA\u3csup\u3eLys\u3c/sup\u3e Phosphatidylglycerol Transferase Activity
In some bacteria Lys-tRNALys is used both in translation and for the specific addition of Lys to phosphatidylglycerol in the cytoplasmic membrane. This reaction is catalyzed by the membrane protein MprF, and the lysyl-phosphatidylglycerol formed contributes to the resistance of these bacteria to various cationic antibacterial molecules. Obtaining proteins and reconstituting an in vitro system mimicking membrane conditions is a major challenge to studying the function of membrane proteins, especially when labile substrates such as Lys-tRNALys are required. Here we report methods to obtain a stable enriched membrane fraction containing MprF, and the techniques necessary to quantitatively monitor its activity in vitro and in vivo
Transfer RNA Comes of Age
The year the journal RNA was founded was slated by some in scientific publishing to be the year that one particular type of RNA\u27s run in the spotlight would end. In 1995 I had recently started as a post-doc with Dieter Söll at Yale when he came into the lab to solemnly inform us all that an editor at a certain (S)cience journal had just told him âwe won\u27t be publishing any more tRNA papers.â For a post-doc who had migrated across the Atlantic for the sole purpose of furthering his career by working on tRNA this was not great news, but at least the pizza was as good as promised in New Haven (if you need convincing, try the Italian and Veggie Bombs at Modern Apizza on State Street). Dieter consoled us by saying that plenty of other good journals were still interested in tRNA, plus there was this
An aminoacyl-tRNA synthetase:elongation factor complex for substrate channeling in archaeal translation
Translation requires the specific attachment of amino acids to tRNAs by aminoacyl-tRNA synthetases (aaRSs) and the subsequent delivery of aminoacyl-tRNAs to the ribosome by elongation factor 1 alpha (EF-1α). Interactions between EF-1α and various aaRSs have been described in eukaryotes, but the role of these complexes remains unclear. To investigate possible interactions between EF-1α and other cellular components, a yeast two-hybrid screen was performed for the archaeon Methanothermobacter thermautotrophicus. EF-1α was found to form a stable complex with leucyl-tRNA synthetase (LeuRS; KD = 0.7 ÎŒM). Complex formation had little effect on EF-1α activity, but increased the kcat for Leu-tRNALeu synthesis âŒ8-fold. In addition, EF-1α co-purified with the archaeal multi-synthetase complex (MSC) comprised of LeuRS, LysRS and ProRS, suggesting the existence of a larger aaRS:EF-1α complex in archaea. These interactions between EF-1α and the archaeal MSC contribute to translational fidelity both by enhancing the aminoacylation efficiencies of the three aaRSs in the complex and by coupling two stages of translation: aminoacylation of cognate tRNAs and their subsequent channeling to the ribosome
The Pros of Changing tRNA Identity
The notion that errors in protein synthesis are universally harmful to the cell has been questioned by findings that suggest such mistakes may sometimes be beneficial. However, how often these beneficial mistakes arise from programmed changes in gene expression as opposed to reduced accuracy of the translation machinery is still unclear. A new study published in JBC shows that some bacteria have beneficially evolved the ability to mistranslate specific parts of the genetic code, a trait that allows improved antibiotic resistance
Effetti dell'allenamento intermittente breve ad alta intensitĂ e delle ripetute aerobiche sul Test Repeated Sprint Ability in giovani calciatori d'elite
The purpose of this study is to evaluate the effects of two different training methods:
the repeated aerobic bouts and the short intermittent high intensity workout on the
ability to carry out repeated sprint bouts RSA in a group of young soccer players and
also to determine the impact of training on aerobic and neuromuscular performances.
Twenty-Four (24) male soccer players have been assessed and trained, all of them
partecipating regularly in the 2013-2014 season at the National Championship
"Professional Development Phase" (Allievi Professionisti) with Cagliari Calcio SPA
Football Club. Hereinafter the anthropometric characteristics of the sample tested:
16.33 ± 0.49 years, height 175 ± 6.3, 65.8 ± 6.8 weight.
The 24 athletes were randomly included into two working groups: intermittent training
group (HI. No. 12) and repeated aerobic exercise group (R. Aer. No. 12). Players
underwent two separate sessions of evaluation tests. During the first session, in the
morning, the players performed the vertical jump test (CMJ) with no counter
movement (SJ). In the afternoon session the repeated sprint bouts were carried out
(RSA). Finally the next day the athletes underwent the tests for the aerobic power
(V.BILLAT).
The results regarding the Aerobic Group (R. Aer.) were respectively SJ and CMJ at T0
36,95 ± 4,03cm; 37,44 ± 4,09cm; T1 to 37.99 ± 3.69 cm; 38.63 ± 3.96 cm;
in the RSA tests we obtained the following T0 and T1 values respectively: 7.690 ± 0.12
s; 7,585 ± 0,11s;
The Billat test instead highlighted the following values ± 1506 67,26m; 1596.6 ±
64,95m. The results regarding the Intermittent (HI) group were respectively SJ and
CMJ at T0 36,69 ± 4,99cm; 37,98 ± 3,97cm; T1 to 38.15 ± 4.79 cm; 39.79 ± 3.78 cm;
in the RSA tests we obtained the following T0 and T1 values respectively: 7.64 ± 0.11
s; 7.31 ± 0,11s; The Billat test instead highlighted the following values: 1537.3 ±
77,70m; 1627.1 ± 72,29m. The results indicate one or more variations of the
investigated capacities between pre and post workout within the same group, and also
suggest that by comparing the two methods, intermittent and repeated aerobic, the first
of the two was more effective. The lack of a statistically significant difference on the
capacity of aerobic performance evaluated through the Billat test suggests that both
protocols have their validity in improving this component. While as regards the RSA
test a statistically significant change was detected in favor of the intermittent protocol
with respect to the repeated aerobic bouts. This variation was found through the
reduction of the average execution time of the RSA test. Another result emerged from
the statistical analysis is that both training protocols had no negative effects on
neuromuscular skills assessed through the vertical jump test of the SJ and CMJ, this in
agreement with what was found in previous studies such as Mc Millan (2005) and
Ferrari (2007), in which training protocols for the aerobic performance of the player
very similar to those used in this study were carried out. In conclusion the study
indicated that the short high intensity intermittent method has proved more powerful
than the Repeated Sprint Ability Test (RSA), which is indicated by most researchers
as a key skill in football performance: we believe it respects mostly the kinematic
analogies of the game, accelerations, decelerations and postural situations with minor
variations of the bust concerning the various stages of the player's running (Paradisis
GP. e coll. 2001) by an increased recruitment of the fast fibers in the rapid typical
accelerations/decelerations of this sport. Furthermore we are inclined to hypothesize
that this research reshapes the use of bioenergetic systems, already studied by (Dawson
B. and coll. 1998), (to Ross, et al. 2001), it all along with the possibility of repeating
the sprint at a high intensity with partial recoveries while maintaining a high quality
and the considerable advantage, being soccer a situational sport, to help keep up a
greater lucidity from a cognitive point of view and theoretically to select more logical
and tactically effective choices
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