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21.
In this study, we quantitatively compared the impact of mission-oriented research grants and curiosity-driven grants on the diversity of research subjects in Japan. First, we examined data for Japanese principal investigators receiving research funding between 2000 and 2010 in the field of nanotechnology and materials science, and identified groups of researchers whose publication performance was positively affected by the mission-oriented grant, CREST. We then compared the effect of CREST with that of the curiosity-driven grant, KAKENHI. The analysis uses both propensity score matching and difference in differences (PSM-DID) methodologies. Our results show that for participants in the CREST program there was an increase in number of publications of more than 10% per year, for periods of both 5 and 3 years after the funding ended, even though the observed average effect on citation was not statistically significant. Second, we evaluated the diversity of research subjects through analysis of the distribution of the classification codes applied to articles published between 1996 and 2013, utilizing the J-Global database, which has the finest granularity of category among existing bibliographic scientific publication databases. Research subjects were better conserved under the mission-oriented program than the curiosity-driven one, a finding contrary to predictions of conventional theory. We also found that under mission-oriented funding, there was an increase in diversity in the sense of marginal utility. These findings should be of use in the “diversity-aware” design of programs for the funding of fundamental research. 相似文献
22.
Flexible aliphatic poly(isocyanurate–oxazolidone) resins based on poly(ethylene glycol) diglycidyl ether and 4,4′‐methylene dicyclohexyl diisocyanate
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Ahmed Bakry Renato Aversano Lucio D'Ilario Valerio Di Lisio Iolanda Francolini Antonella Piozzi Andrea Martinelli 《应用聚合物科学杂志》2016,133(19)
New flexible aliphatic oxazolidone‐isocyanurate networks (AISOX) are obtained by reacting a low molecular weight diisocyanate (4,4′‐methylene dicyclohexyl diisocyanate, H12MDI) and a macro‐diepoxyde (poly(ethylene glycol) diglycidyl ether, Mn = 526, PEGDGE) in different molar ratio. The curing reaction, carried out from 25 °C to 200 °C, is studied by using DSC and FTIR. The effect of the molar ratio of the two monomers on thermal and mechanical properties of AISOX resins is investigated by DSC, thermogravimetric analysis, stress?strain measurements and optical microscopy. Independently from the feed composition, it is observed that the reaction steps are: (i) partial hydrolysis of isocyanate caused by water traces, (ii) incomplete trimerization of isocyanate to give isocyanurate, and (iii) formation of oxazolidone and complete conversion of isocyanate. At the highest concentration of the soft macrodiepoxyde (PEGDGE), the AISOX resin is in the rubbery state at room temperature and shows an elastomeric behavior. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43404. 相似文献
23.
Angelo G. Giumanini Giancarlo Verardo Lucio Randaccio Nevenka Bresciani-Pahor Pietro Traldi 《Advanced Synthesis \u0026amp; Catalysis》1985,327(5):739-748
A rapid and efficient preparation of 1,3,5-triphenylhexahydro-sym-triazine ( 10 ) using paraformaldehyde is reported. The trimeric nature of the compound and its structure in solid state, where a biaxial chair conformation is favoured, are conclusively shown by X-ray diffraction analysis. A recent report on a preparation of 1,3-diphenyl-1,3-diazetidine is invalidated. 相似文献
24.
Giulia Sierri Roberta Dal Magro Barbara Vergani Biagio Eugenio Leone Beatrice Formicola Lorenzo Taiarol Stefano Fagioli Marcelo Kravicz Lucio Tremolizzo Laura Calabresi Francesca Re 《International journal of molecular sciences》2022,23(1)
The cerebral synthesis of cholesterol is mainly handled by astrocytes, which are also responsible for apoproteins’ synthesis and lipoproteins’ assembly required for the cholesterol transport in the brain parenchyma. In Alzheimer disease (AD), these processes are impaired, likely because of the astrogliosis, a process characterized by morphological and functional changes in astrocytes. Several ATP-binding cassette transporters expressed by brain cells are involved in the formation of nascent discoidal lipoproteins, but the effect of beta-amyloid (Aβ) assemblies on this process is not fully understood. In this study, we investigated how of Aβ1-42-induced astrogliosis affects the metabolism of cholesterol in vitro. We detected an impairment in the cholesterol efflux of reactive astrocytes attributable to reduced levels of ABCA1 transporters that could explain the decreased lipoproteins’ levels detected in AD patients. To approach this issue, we designed biomimetic HDLs and evaluated their performance as cholesterol acceptors. The results demonstrated the ability of apoA-I nanodiscs to cross the blood–brain barrier in vitro and to promote the cholesterol efflux from astrocytes, making them suitable as a potential supportive treatment for AD to compensate the depletion of cerebral HDLs. 相似文献
25.
Stefano Ravaioli Davide Campoccia Werner Ruppitsch Franz Allerberger Alessandro Poggi Emanuele Chisari Lucio Montanaro Carla Renata Arciola 《International journal of molecular sciences》2022,23(3)
108 isolates of Staphylococcus aureus, belonging to six large ribogroups according to the automated Ribo-Printer® system, were studied with two highly used molecular methods for epidemiological studies, namely multi-locus sequence typing (MLST) and spa typing, followed by BURP and eBURST v3 analysis for clustering spa types and sequence (ST) types. The aim was to evaluate whether automated ribotyping could be considered a useful screening tool for identifying S. aureus genetic lineages with respect to spa typing and MLST. Clarifying the relationship of riboprinting with these typing methods and establishing whether ribogroups fit single clonal complexes were two main objectives. Further information on the genetic profile of the isolates was obtained from agr typing and the search for the mecA, tst genes, and the IS256 insertion sequence. Automated ribotyping has been shown to predict spa clonal complexes and MLST clonal complexes. The high cost and lower discriminatory power of automated ribotyping compared to spa and MSLT typing could be an obstacle to fine genotyping analyzes, especially when high discriminatory power is required. On the other hand, numerous advantages such as automation, ease and speed of execution, stability, typeability and reproducibility make ribotyping a reliable method to be juxtaposed to gold standard methods. 相似文献
26.
Gregory L. Olsen Adonis Lupulescu Jean-Nicolas Dumez Lyndon Emsley Lucio Frydman 《Israel journal of chemistry》2014,54(1-2):154-162
Line narrowing has been traditionally achieved in solid-state 1H NMR spectroscopy by applying pulse sequences that combine multiple-pulse operations with magic-angle spinning (MAS), to effectively average out the dipole dipole homonuclear Hamiltonian. The present study explores a new alternative that departs from the usual concept of directly acting on the strongly coupled spins with radiofrequency pulses; instead, we seek to achieve a net homonuclear dipolar decoupling in solids by exploring the reintroduction of MAS-averaged heteronuclear dipolar couplings between the 1H nuclei and directly bonded 13C or 15N nuclei. This recoupling anti-recoupling (RaR) scheme thus relies on the recoupling of the dipolar interaction with heteronuclear spins, which, under fast MAS, will exceed the strength and will not commute with the homonuclear 1H 1H coupling one is intending to average out. Subsequent removal (“antiRecoupling”) of these heteronuclear interactions can lead to narrowed 1H resonances, without ever pulsing on the aforementioned channel. The line-narrowing properties of RaR are illustrated with numerical simulations and with experiments on model organic solids. 相似文献
27.
Kresimir Dabcevic Muhammad Ozair Mughal Lucio Marcenaro Carlo S. Regazzoni 《Journal of Signal Processing Systems》2016,83(1):29-44
Throughout the 1990s, Software Defined Radio (SDR) technology was viewed almost exclusively as a solution for interoperability problems between various military standards, waveforms and devices. In the meantime, Cognitive Radio (CR) – a novel communication paradigm which embodies SDR with intelligence and self-reconfigurability properties – has emerged. Intelligence and on-the-fly self-reconfiguration abilities of CRs constitute an important next step in the Communications Electronic Warfare, as they may enable the jamming entities with the capabilities of devising and deploying advanced jamming tactics. Similarly, they may also aid the development of the advanced intelligent self-reconfigurable systems for jamming mitigation. This work outlines the development and implementation of the Spectrum Intelligence algorithm for Radio Frequency (RF) interference mitigation. The developed system is built upon the ideas of obtaining relevant spectrum-related data by using wideband energy detectors, performing narrowband waveform identification, extracting the waveforms’ parameters and properly classifying the waveforms. All relevant spectrum activities are continuously monitored and stored. Coupled with the self-reconfigurability of various transmission-related parameters, Spectrum Intelligence is the facilitator for the advanced interference mitigation strategies. The implementation is done on the Cognitive Radio test bed architecture which consists of two military Software Defined Radio terminals, each interconnected with the computationally powerful System-on-Module. 相似文献
28.
Reinaldo Barros Geraldo Plínio Cunha Sathler André Luiz Louren?o Max Seidy Saito Lucio M. Cabral Pabulo Henrique Rampelotto Helena Carla Castro 《International journal of molecular sciences》2014,15(10):17901-17919
Platelets are cytoplasmatic fragments from bone marrow megakaryocytes present in blood. In this work, we review the basis of platelet mechanisms, their participation in syndromes and in arterial thrombosis, and their potential as a target for designing new antithrombotic agents. The option of new biotechnological sources is also explored. 相似文献
29.
This article proposes an analytical model for evaluating the number of simultaneous communications that can be sustained by
an ad-hoc network in which the nodes are equipped with fully adaptive smart antennas. The presented mathematical framework
adopts realistic models for the antenna radiation pattern and the channel behavior, and is able to take into account the network
topology and the characteristics of the medium access control (MAC) protocol in the spatial domain. The model is employed
to investigate the impact of the spatial channel model and of the angular spread on network performance. Additionally, this
article examines the influence of the transmission policy of the control and data packets of the MAC layer on the number of
simultaneous communications. 相似文献
30.
Paola Bonizzoni Gianluca Della Vedova Riccardo Dondi Giancarlo Mauri 《Algorithmica》2010,58(2):282-303
The problem of clustering fingerprint vectors with missing values is an interesting problem in Computational Biology that
has been proposed in Figueroa et al. (J. Comput. Biol. 11(5):887–901, 2004). In this paper we show some improvements in closing the gaps between the known lower bounds and upper bounds on the approximability
of variants of the biological problem. Moreover, we have studied two additional variants of the original problem proposed
in Figueroa et al. (Proc. 11th Computing: The Australasian Theory Symposium (CATS), CRPIT, vol. 41, pp. 57–60, 2005). We prove that all such problems are APX-hard even when each fingerprint contains only two unknown positions and we present
a greedy algorithm that has constant approximation factors for these variants. Despite the hardness of these restricted versions
of the problem, we show that the general clustering problem on an unbounded number of missing values such that they occur
for every fixed position of an input vector in at most one fingerprint is polynomial time solvable. 相似文献