80 resultados para yield per recruit


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Il tema dei servizi pubblici locali è sicuramente centrale nell'attuale contesto socio-economico nazionale ed internazionale, in quanto essi hanno un impatto determinante sulle condizioni di vita dei cittadini e sulla competitività dei sistemi economici. In ragione di ciò, negli ultimi anni in Italia numerose riforme si sono susseguite, con lo scopo di individuare l'assetto più efficace ed efficiente per tale settore. Le suddette riforme hanno così ridisegnato il ruolo degli Enti Locali, che saranno sempre meno gestori diretti e sempre più direttori di una multiforme orchestra composta dalle aziende esterne chiamate a fornire in prima persona le prestazioni agli utenti finali. Il presente lavoro si propone di individuare, anche attraverso una ricerca sui Comuni capoluogo di Emilia-Romagna e Toscana, strumenti di programmazione e controllo in ottica di gruppo che consentano agli Enti Locali di svolgere questo nuovo delicato ruolo. Tali strumenti verranno disegnati sulla base delle necessità informative delle amministrazioni indagate e nel rispetto delle più recenti riforme in tema di programmazione, rilevazione, gestione, controllo, valutazione e comunicazione delle performance pubbliche.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Purpose. To develop a protocol for isolating and culturing murine adult retinal microglia and to characterize the phenotype and function of the cultured cells. Method. Retinal single-cell suspensions were prepared from adult MF1 mice. Culture conditions including culture medium, growth factors, seeding cell density, and purification of microglia from the mixed cultures were optimised. Cultured retinal microglial cells were phenotyped using the surface markers CD45, CD11b, and F4/80. Their ability to secrete proinflammatory cytokines in response to lipopolysaccharide (LPS) stimulation was examined using cytometric bead array (CBA) assay. Results. Higher yield was obtained when retinal single-cell suspension was cultured at the density of cells per cm2 in Dulbecco’s modified Eagle medium (DMEM)/F12 + Glutamax supplement with 20% fetal calf serum (FCS) and 20% L929 supernatant. We identified day 10 to be the optimum day of microglial isolation. Over 98% of the cells isolated were positive for CD45, CD11b, and F4/80. After stimulating with LPS they were able to secrete proinflammatory cytokines such as IL-6 and TNF-α and express CD86, CD40, and MHC-II. Conclusion. We have developed a simple method for isolating and culturing retinal microglia from adult mice.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In this paper we propose a design methodology for low-power high-performance, process-variation tolerant architecture for arithmetic units. The novelty of our approach lies in the fact that possible delay failures due to process variations and/or voltage scaling are predicted in advance and addressed by employing an elastic clocking technique. The prediction mechanism exploits the dependence of delay of arithmetic units upon input data patterns and identifies specific inputs that activate the critical path. Under iso-yield conditions, the proposed design operates at a lower scaled down Vdd without any performance degradation, while it ensures a superlative yield under a design style employing nominal supply and transistor threshold voltage. Simulation results show power savings of upto 29%, energy per computation savings of upto 25.5% and yield enhancement of upto 11.1% compared to the conventional adders and multipliers implemented in the 70nm BPTM technology. We incorporated the proposed modules in the execution unit of a five stage DLX pipeline to measure performance using SPEC2000 benchmarks [9]. Maximum area and throughput penalty obtained were 10% and 3% respectively.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The absolute yield of hydroxyl radicals per unit of deposited X-ray energy is determined for the first time for irradiated aqueous solutions containing metal nanoparticles based on a “reference” protocol. Measurements are made as a function of dose rate and nanoparticle concentration. Possible mechanisms for hydroxyl radical production are considered in turn: energy deposition in the nanoparticles followed by its transport into the surrounding environment is unable to account for observed yield whereas energy deposition in the water followed by a catalytic-like reaction at the water-nanoparticle interface can account for the total yield and its dependence on dose rate and nanoparticle concentration. This finding is important because current models used to account for nanoparticle enhancement to radiobiological damage only consider the primary interaction with the nanoparticle, not with the surrounding media. Nothing about the new mechanism appears to be specific to gold, the main requirements being the formation of a structured water layer in the vicinity of the nanoparticle possibly through the interaction of its charge and the water dipoles. The massive hydroxyl radical production is relevant to a number of application fields, particularly nanomedicine since the hydroxyl radical is responsible for the majority of radiation-induced DNA damage.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Monte Carlo calculations of quantum yield in PtSi/p-Si infrared detectors are carried out taking into account the presence of a spatially distributed barrier potential. In the 1-4 mu m wavelength range it is found that the spatial inhomogeneity of the barrier has no significant effect on the overall device photoresponse. However, above lambda = 4.0 mu m and particularly as the cut-off wavelength (lambda approximate to 5.5 mu m) is approached, these calculations reveal a difference between the homogeneous and inhomogeneous barrier photoresponse which becomes increasingly significant and exceeds 50% at lambda = 5.3 mu m. It is, in fact, the inhomogeneous barrier which displays an increased photoyield, a feature that is confirmed by approximate analytical calculations assuming a symmetric Gaussian spatial distribution of the barrier. Furthermore, the importance of the silicide layer thickness in optimizing device efficiency is underlined as a trade-off between maximizing light absorption in the silicide layer and optimizing the internal yield. The results presented here address important features which determine the photoyield of PtSi/Si Schottky diodes at energies below the Si absorption edge and just above the Schottky barrier height in particular.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Abstract. The possibility of using pumice aggregates for concrete in structural applications is discussed. In particular, the mix design of lightweight concrete for the manufacturing masonry units having proper strength, is discussed. Moreover, the design of the unit shape according to the technical code requirements and making it possible to arrange reinforcing steel bars is described. Reinforced bearing masonry walls, made with the concrete units in question, were manufactured and tests on the panels and on the designed units were carried out. For comparison, tests on concrete units and structural elements were carried out after the substitution of pumice aggregates with ordinary lightweight aggregates, proving that pumice can be considered an alternative to them. Sommario. L’uso della pomice come inerte per il confezionamento di calcestruzzo è poco diffuso sebbene essa sia stata usata già in antiche costruzioni come il Pantheon in Roma. In questo studio si affronta la possibilità di realizzare blocchi in calcestruzzo alleggerito con granuli di pomice. I blocchi, progettati e realizzati secondo le indicazioni normative correnti, sono stati usati per realizzare pannelli murari armati da sottoporre a carichi ciclici orizzontali. I risultati ottenuti, messi a confronto con quelli di pannelli realizzati con blocchi in cls alleggerito con argilla espansa, hanno mostrato la possibilità di utilizzare la pomice come validissima alternativa all’argilla espansa.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This work comprises the photoactivity assessment of transparent sol–gel TiO2 coatings of various thickness using two test systems. The initial rates of both photocatalytic reactions, namely the oxidative bleaching of Acid Orange 7 (AO7) and the reductive bleaching of 2,6-dichlorindophenol (DCIP) increase linearly with increasing titania film thickness as well as with increasing absorbed light flux. The latter work revealed quantum yields (QY) of 0.19% and 92% for the AO7 and DCIP test system, respectively. The low QY for the AO7 oxidation is due to the combination of a slow irreversible reduction of oxygen and also for the oxidation of AO7, thus favouring the high efficiency for electron–hole recombination that is typical for aqueous organic pollutants. In contrast, the very high QY for the photocatalysed reduction of DCIP is due to the presence of a vast excess of glycerol which traps the photogenerated holes efficiently and so allow time for the slower reduction of dye to take place. Furthermore, the oxidation of glycerol results in the generation of highly reducing R-hydroxyalkyl radicals that are able to also reduce DCIP. As a consequence of this ‘current doubling’ effect, the observed QY (92%) is much higher than the apparent theoretical value of 50%.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Benzene cis-diol dehydrogenase and naphthalene cis-diol dehydrogenase enzymes, expressed in Pseudomonas putida wild-type and Escherichia coli recombinant strains, were used to investigate regioselectivity and stereoselectivity during dehydrogenations of arene, cyclic alkane and cyclic alkene vicinal cis-diols. The dehydrogenase-catalysed production of enantiopure cis-diols, α-ketols and catechols, using benzene cis-diol dehydrogenase and naphthalene cis-diol dehydrogenase, involved both kinetic resolution and asymmetric synthesis methods. The chemoenzymatic production and applications of catechol bioproducts in synthesis were investigated.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Two experiments were conducted to examine the ‘long-term’ effect of feed space allowance and period of access to feed on dairy cow performance. In Experiment 1, three horizontal feed space allowances (20, 40 and 60 cm cow−1) were examined over a 127-d period (14 cows per treatment). In Experiment 2, 48 dairy cows were used in a continuous design (10-week duration) 2 × 2 factorial design experiment comprising two horizontal feed space allowances (15 and 40 cm cow−1), and two periods of access to feed (unrestricted and restricted). With the former, uneaten feed was removed at 08·00 h, while feeding took place at 09·00 h. With the latter, uneaten feed was removed at 06·00 h, while feeding was delayed until 12·00 h. Mean total dry-matter (DM) intakes were 19·0, 18·7 and 19·3 kg cow−1 d−1 with the 20, 40 and 60 cm cow−1 treatments in Experiment 1, and 18·1 and 18·2 kg cow−1 d−1 with the ‘restricted feeding time’ treatments, and 17·8 and 18·1 kg d−1 with the ‘unrestricted feeding time’ treatments (15 and 40 cm respectively) in Experiment 2. None of milk yield, milk composition, or end-of-study live weight or condition score were significantly affected by treatment in either experiment (P > 0·05), while fat + protein yield was reduced with the 15-cm treatment in Experiment 2 (P < 0·05). When access to feed was restricted by space or time constraints, cows modified their time budgets and increased their rates of intake.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Quantum yields of the photocatalytic degradation of methyl orange under controlled periodic illumination (CPI) have been modelled using existing models. A modified Langmuir-Hinshelwood (L-H) rate equation was used to predict the degradation reaction rates of methyl orange at various duty cycles and a simple photocatalytic model was applied in modelling quantum yield enhancement of the photocatalytic process due to the CPI effect. A good agreement between the modelled and experimental data was observed for quantum yield modelling. The modified L-H model, however, did not accurately predict the photocatalytic decomposition of the dye under periodic illumination.