338 research outputs found
Synthesis of [(1,2,3-Triazol-1-yl)methyl]boronic Acids Through Click Chemistry: Easy Access to a Potential Scaffold for Protease Inhibitors
Stereoselective synthesis of previously unreported [(1,2,3-triazol-1-yl)methyl]boronic acids has been achieved from azidomethylboronates by copper-catalyzed azide–alkyne cycloaddition reaction. The proximity of the cycloaddition reaction center to the boronic group is not detrimental to the stability of the sp3 C–B bond or to the stereoisomeric composition, which further expands the field of application of click chemistry to new boronate substrates and offers a new potential scaffold for protease inhibitors
An efficient and versatile synthesis of new Trojan-horse cephalosporins
A useful synthesis of new dual-action cephalosporins is reported. These molecules could represent a fascinating tool for treatment of bacterial infectious diseases, since they display a possible inhibitor activity towards beta-lactamase-expressing bacteria. The major advantage of this 3-step synthetic approach lies in its versatility, which allows the systematic preparation of a wide pool of new molecules
Higher-Order Permanent Scatterers Analysis
The permanent scatterers (PS) technique is a multi-interferogram algorithm for DInSAR analyses developed in the late nineties to overcome the difficulties related to the conventional approach, namely, phase decorrelation and atmospheric effects. The successful application of this technology to many geophysical studies is now pushing toward further improvements and optimizations. A possible strategy to increase the number of radar targets that can be exploited for surface deformation monitoring is the adoption of parametric super-resolution algorithms that can cope with multiple scattering centres within the same resolution cell. In fact, since a PS is usually modelled as a single pointwise scatterer dominating the background clutter, radar targets having cross-range dimension exceeding a few meters can be lost (at least in C-band datasets), due to geometrical decorrelation phenomena induced in the high normal baseline interferograms of the dataset. In this paper, the mathematical framework related to higher-order SAR interferometry is presented as well as preliminary results obtained on simulated and real data. It is shown how the PS density can be increased at the price of a higher computational load
Cardiorespiratory and gastrointestinal parasites of dogs in north-west Italy
The present study was conducted to evaluate the prevalence of gastrointestinal and cardio-respiratory
parasites in dogs in Liguria (northwest Italy) which is a region that has scarcely been studied. A
total of 450 dogs (260 males and 190 females) were enrolled in the study from 2009 and 2013. All
dogs lived in a rural or semi-rural environment in the provinces of Imperia (n = 352) or Savona (n =
98), Liguria. Coprological examinations showed that 197 dogs (43.8 %, CI 38.7-48.9 %) were infected
by parasites. Specifi cally, 3.3 % of the dogs presented only cardio-respiratory species, 32.4 %
only intestinal species, and 8.0 % presented a mixed infection.
The most frequent intestinal parasites were Toxocara canis (20 %), Trichuris vulpis (17.8 %), Ancylostomatidae
(12 %), Coccidia (2.7 %), Aonchotheca putorii (1.8 %) and Toxascaris leonina (1.8 %).
The cardio-respiratory species found were Eucoleus aerophilus (9.6 %), Eucoleus boehmi (1.6 %),
Angiostrongylus vasorum (0.7 %), and Crenosoma vulpis (0.2 %). A total of 116 dogs (25.8 %) were
parasitized by a single species, multiple infections were observed in 81 dogs (18.0 %) up to a six-order
infection.
This preliminary study highlighted that the prevalence of intestinal parasites in investigated area is
high. Cardio respiratory parasites were detected in an area that has not been investigated before.
The creation of a more extensive sampling programme of the area, on a provincial basis in order to
build a more detailed map of prevalences for different species of dog parasites throughout Liguria, a
more extensive sampling programme of the area needs to be created - ideally for each province
Anonymous crypt P2P. A model for a secure and private communication
The aim of this work is to contribute to the modelling of a peer-to-peer protocol in order to fill a lack that still remains in the wide panorama of developed model, i.e. .e. a deterministic anonymous and crypt peer-to-peer communication system. This work considers first the most important model confirmed by the diffusion and the reliability for their purposes, presenting an overview that focuses on the main characteristics. Than an analysis of the requirements is done and two different strategies are analysed, building two models for different anonymity and security levels. The two models are discussed and a communication protocol for a minimal user client interface is described. Finally the scalability problem is discussed
Intraspecific competition among larvae of Aedes albopictus in conditions of food abundance and shortage
The competition between larvae of Aedes albopictus (Skuse, 1987), an invasive mosquito species recently established in Italy, was evaluated in laboratory in conditions of food abundance and shortage. The number of emerging adults, the time of emergence and the size of the adult bodies were recorded and compared. The number of adults that emerge under conditions of food abundance was found to be significantly higher than under food shortage. When food was lacking more males than females emerged and there was no significant difference in their body sizes, while under food abundance females were larger than males. Both males and females with abundant food were on average bigger than under food shortage. There was no difference in the time of adult emergence in the two different food condition
Assessment of ambient air quality in the port of Naples
Two experimental monitoring campaigns were carried out in 2012 to investigate the air quality in the port of Naples, the most
important in southern Italy for traffic of passengers and one of the most important for goods. Therefore, it represents an
important air pollution source located close to the city of Naples. The concentrations of sulfur dioxide (SO2), nitrogen dioxide
(NO2), and BTEX (benzene, toluene, ethylbenzene, and xylenes) in the air were measured at 15 points inside the Naples port area
through the use of passive samplers. In addition, a mobile laboratory was positioned in a fixed point inside the port area to
measure continuous concentration of pollutants together with particulate matter, ambient parameters, and wind direction and
intensity. The pollution levels monitored were compared with those observed in the urban area of Naples and in other
Mediterranean ports. Even though the observation time was limited, measured concentrations were also compared with limit
values established by European legislation. All the measured pollutants were below the limits with the exception of nitrogen
dioxide: its average concentration during the exposition time exceeded the yearly limit value. A spatial analysis of data,
according to the measured wind direction and intensity, provided information about the effects that ship emissions have on
ambient air quality in the port area. The main evidence indicates that ship emissions influence sulfur dioxide concentration more
than any other pollutants analyze
Optical Time-Frequency Packing: Principles, Design, Implementation, and Experimental Demonstration
Time-frequency packing (TFP) transmission provides the highest achievable
spectral efficiency with a constrained symbol alphabet and detector complexity.
In this work, the application of the TFP technique to fiber-optic systems is
investigated and experimentally demonstrated. The main theoretical aspects,
design guidelines, and implementation issues are discussed, focusing on those
aspects which are peculiar to TFP systems. In particular, adaptive compensation
of propagation impairments, matched filtering, and maximum a posteriori
probability detection are obtained by a combination of a butterfly equalizer
and four 8-state parallel Bahl-Cocke-Jelinek-Raviv (BCJR) detectors. A novel
algorithm that ensures adaptive equalization, channel estimation, and a proper
distribution of tasks between the equalizer and BCJR detectors is proposed. A
set of irregular low-density parity-check codes with different rates is
designed to operate at low error rates and approach the spectral efficiency
limit achievable by TFP at different signal-to-noise ratios. An experimental
demonstration of the designed system is finally provided with five
dual-polarization QPSK-modulated optical carriers, densely packed in a 100 GHz
bandwidth, employing a recirculating loop to test the performance of the system
at different transmission distances.Comment: This paper has been accepted for publication in the IEEE/OSA Journal
of Lightwave Technolog
Fishes and their parasites in the water district of Massaciuccoli (Tuscany, Central Italy)
This study has been conducted in the district of Massaciuccoli (lake, marsh and reclaimed areas with drainage channels) in Tuscany region (Central Italy). The aim of the research was to detect the presence of parasites in fishes, in particular of Opisthorchis felineus, which causes an important zoonosis. Between 2010-2012, the health status of 381 fishes was monitored, morphometric characteristics were determined, and parasites were searched for and identified. Of the 381 examined fishes, 189 were free of parasites while 192 were infected, among them 91 presented multiple infections. Opisthorchis felineus was not found in any of the examined fishes
UX Evaluation of a Tractor Cabin Digital Twin Using Mixed Reality
Understanding user experience (UX) is essential to design engaging and attractive products, so nowadays has emerged an increasingly interest in user- centred design approach; in this perspective, digital technologies such as Virtual Reality (VR) and Mixed Reality (MR) could help designers and engineers to create a digital prototype through which the user feedback can be considered during the product design stage. This research aims at creating an interactive Digital Twin (DT) using MR to enable a tractor driving simulation and involve real users to carry out an early UX evaluation, with the scope to validate the design of the control dashboard through a transdisciplinary approach. MR combines virtual simulation with real physical hardware devices which the user can interact with and have control through both visual and tactile feedback. The result is a MR simulator that combines virtual contents and physical controls, capable of reproducing a plowing activity close to reality. The principles of UX design was applied to this research for a continuous and dynamic UX evaluation during the project development
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