611 research outputs found
Smart load cells: an industrial application
This paper presents a data acquisition solution using a RISC type
microcontroller with a very few components around, taking
advantage of the ratiometric functioning of the load cells. The need
of thermally stable circuits is minimized through
the use of the same amplification chain for both signal and reference.
The amplification and filtering are done trough switched-capacitor
techniques controlled by the microcontroller. This option allows the
choice of the proper scale according to the platform and permits the
auto-calibration of the system.
The weighing tests show errors below 100 gr in 400 kg for an
industrial platform of 8 smart load cells. The paper also describes
an example of software calibration of a multi-load cell weigh-bridge
using one processor per smart load cell
Arylation Of β,γ-unsaturated Lactones By A Heck-matsuda Reaction: An Unexpected Route To Aryldiazene Butenolides And Pyridazinones
The palladium catalysed coupling of aryldiazonium salts with β-γ-unsaturated lactones under basic conditions has been investigated. Both (3H)-furanone and α-angelicalactone were evaluated as substrates in the Heck Matsuda reaction but both failed to afford the desired arylated butenolides. Under basic conditions, β-γ-unsaturated lactones generate highly nucleophilic enolates that preferentially undergo azo coupling reactions with arenediazonium salts to afford aryldiazene butenolides. The electronic and steric effect of the substituents on the aryldiazonium salt in the azo coupling reaction is described. Aryldiazene-lactone derivatives were obtained in good yields from a highly facile and straightforward procedure. An aminoisomaleimide was formed from (3H)-furanone and cyclised to the corresponding pyridazinones in modest yield.331020702074Tsuji, J., (1997) Palladium Reagents and Catalysts: Innovations in Organic Synthesis, , 1st ed., Wiley: LondonShibasaki, M., Vogl, E.M., Ohshima, T., (2004) Adv. Synth. Catal., 346, p. 1533. , For reviews seeDounay, A.B., Overman, L.E., (2003) Chem. Rev., 103, p. 2945Siqueira, F.A., Taylor, J.G., Correia, C.R.D., (2010) Tetrahedron. Lett., 51, p. 2102. , For selected examples seeMoro, A.V., Cardoso, F.S.P., Correia, C.R.D., (2009) Org. Lett., 11, p. 3642Pastre, J.C., Correia, C.R.D., (2009) Adv. Synth. Catal., 351, p. 1217Machado, A.H.L., De Sousa, M.A., Patto, D.C.S., Azevedo, L.F.S., Bombonato, F.I., Correia, C.R.D., (2009) Tetrahedron. Lett., 50, p. 1222Moro, A.V., Cardoso, F.S.P., Correia, C.R.D., (2008) Tetrahedron. Lett., 49, p. 5668Coy, E.D., Jovanovic, L., Sefkow, M., (2010) Org. Lett., 12, p. 1976. , For selected examples seeCacchi, S., Fabrizi, G., Goggiamani, A., Sferrazza, A., (2009) Synlett, 8, p. 1277Bartoli, G., Cacchi, S., Fabrizi, G., Goggiamani, A., (2008) Synlett, 16, p. 2508Barbero, M., Cadamuro, S., Dughera, S., (2006) Synthesis, 20, p. 3443Kikukawa, K., Matsuda, T., (1977) Chem. Lett., p. 159Sengupta, S., Bhattacharyya, S., (2001) Tetrahedron. Lett., 42, p. 2035Kikukawa, K., Nagira, K., Wada, F., Matsuda, T., (1981) Tetrahedron., 37, p. 31Kikukawa, K., Matsuda, T., (1977) Chem. Lett., p. 159Hyde, A.M., Buchwald, S.L., (2009) Org. Lett., 11, p. 2663Szele, I., Zollinger, H., (1983) Top. Curr. Chem., 112, p. 1Otto, D., (1907) Berichte der Deutschen Chemischen Gesellschaft, 40, p. 2404Shapiro, D., Segal, H., Flowers, H.M., (1958) J. Am. Chem., 80, p. 1194. , For examples seeVenturello, C., D'Aloisio, R., (1979) Synthesis, 4, p. 283Garst, M.E., Lukton, D., (1980) Synth. Commun., 10, p. 155Blank, O., Wetzel, A., Ullrich, D., Heinrich, M.R., (2008) Eur. J. Org. Chem., 18, p. 3179Jackson, A., Joule, J.A., (1967) Chem. Commun., 9, p. 459. , For examples seeShawali, A.S., El-Galil, A.M., (1971) Tetrahedron., 27, p. 4305Bestmann, H.J., Schmid, G., Sandmeier, D., (1980) Tetrahedron. Lett., 21, p. 2939Atlan, V., Kaim, L., Supiot, C., (2000) Chem. Commun., 15, p. 1385Tsou, K.C., Barnett, R.J., Seligman, A.M., (1955) J. Am. Chem. Soc., 77, p. 4613. , first aminoisomaleimide synthesis was reported in 1955 by Tsou and formed by intramolecular condensation of an N-substituted maleamic acid using trifuroacetic anhydride as dehydrating agentNaesman, J.A.H., Pensar, K.G., (1985) Synthesis, 8, p. 786Kraus, G.A., Roth, B., (1977) Tetrahedron. Lett., 18, p. 3129. , Dimerisation and polymerisation of butenolides has been previously reportedParnarouskis, M., Rubinstein, H., (1976) J. Heterocycl. Chem., 13, p. 423Meier, K.D., Ringier, B.H., Druey, J., (1954) Helv. Chim. Acta, 37, p. 523Seymour, D., (1955) J. Chem. Soc., p. 852Baloniak, S., Mroczkiewicz, A., Katrusiak, A., (1996) Pol. J. Chem., 70, p. 1274Tartar, A., Melnyk, P., (1996) Tetrahedron. Lett., 37, p. 4145Conley, N.R., Hung, R.J., Willson, C.G., (2005) J. Org. Chem., 70, p. 4553Johnston, A.K., Allcock, R.W., Jiang, Z., Collier, I.D., Blakli, H., Rosair, G.M., Bailey, P.D., Adams, D.R., (2008) Org. Biomol. Chem., 6, p. 175Natarajan, S.R., Heller, S.T., Nam, K., Singh, S.B., Scapin, G., Patel, S., Thompson, J.E., O'Keefe, S.J., (2006) Bioorg. Med. Chem. Lett., 16, p. 5809Dal Piaz, P., Vergelli, C., Castellana, M.C., Gioavannoni, M.P., Pieretti, S., (2002) J. Heterocycl. Chem., 39, p. 523Matyus, P., (1998) J. Heterocycl. Chem., 35, p. 1075Jones, J.B., Barker, J.N., (1970) Can. J. Chem., 48, p. 1574. , This reaction is known to occur under basic conditionsLukes, R., Syhora, K., (1954) Collect. Czech. Chem. Commun., 19, p. 1205David, P., Langlois, H.W., (1948) J. Am. Chem. Soc., 70, p. 2624Herbst, W., Hunger, K., (1978) Prog. Org. Coat, 6, p. 10
Evaluation of Nanoparticle Uptake iii Co-culture Cancer Modeis
Co-culture models are currently bridging the gap between classical cultures and in vivo animal models. Exploring this novel approach unlocks the possibility to mimic the tumor microenvironment in vitro, through the establishment of cancer-stroma synergistic interactions. Notably, these organotypic models offer a perfect platform for the development and pre-clinical evaluation of candidate nanocarriers loaded with anti-tumoral drugs in a high throughput screening mode, with lower costs and absence of ethical issues. However, this evaluation was until now limited to co-culture systems established with precise cell ratios, not addressing the natural cell heterogeneity commonly found in different tumors. Therefore, herein the multifunctional nanocarriers efficiency was characterized in various fibroblast-MCF-7 co-culture systems containing different cell ratios, in order to unravel key design parameters that influence nanocarrier performance and the therapeutic outcome. The successful establishment of the co-culture models was confirmed by the tissue-like distribution of the different cells in culture. Nanoparticles incubation in the various co-culture systems reveals that these nanocarriers possess targeting specificity for cancer cells, indicating their suitability for being used in this illness therapy. Additionally, by using different co-culture ratios, different nanoparticle uptake profiles were obtained. These findings are of crucial importance for the future design and optimization of new drug delivery systems, since their real targeting capacity must be addressed in heterogenous cell populations, such as those found in tumors.PEst-OE/EGEJUI4D5G/201
CMOS x-rays detector array based on scintillating light guides
This paper describes a pixel imaging array consisting in
400µm x 400µm photodiodes fabricated in CMOS technology.
An array of scintillating CsI:Tl crystals is placed above the
photodiodes. These crystals are encapsulated in aluminum walls, forming
a light path that guides the visible light produced by the
scintillating crystal into the photodiodes. In This way, the x-ray
energy is first converted into visible light which is then detected by
the photodiode at the end of
each light guide. The scintillator is 800 µm thick, absorbing
almost all 20keV x-ray photons.
Usually, the spatial resolution of the scintillating x-ray detectors
is identical to the scintillator thickness. By using the
light guides, the scintillator thickness can be increased
without decreasing the spatial resolution.
The increase of the scintillator thickness is desirable in order
to increase the x-rays absorption efficiency.
Tests carried out on the system show very promising results near
20keV
The striped soldier shrimp Plesionika edwardsii (Crustacea:Decapoda:Pandalidae) from the cape Verde Islands
This study is part of the PROACTIVA 1-2 (2009-2012) and MARPROF-CV (2010-2014) projects, in the
framework of the Canary Islands Government and UE PCT MAC 2007-2013 programmes respectively.
Research has mainly focused on the stock assessment of the striped soldier shrimp, Plesionika edwardsii
(Brandt, 1851), because it has shown moderate to high levels of fishing yield and abundances compatible
with the development of a new sustainable fishery in the Cape Verde Islands.
Cruises took place on board the R/V Prof. Ignacio Lozano. Four 15-day surveys have been conducted to
date: Cabo Verde 2010-04 (April 2010), CamarËśao-1 (November 2011), CamarËśao-2 (Mars 2012) and Camar
Ëśao-3 (July 2012). An innovative fishing gear so-called multiple semi-floating shrimp trap (MSFST)
was used. Each fishing line was composed by 40-65 traps operating around 2.4 m above the seafloor,
using Decapterus macarellus (Carangidae) as unique bait of the traps. Fishing depth was 66-458 m, and
efective fishing time was 16-18 h. Each trap was attached to the main bottom line every 15 m, and the
maximum attraction of this bait was established to be 100 or 150 m, according to the experience gained
from the local fishery for deep-sea lobsters. So density by area was calculated assuming two different
areas of attraction of the fishing gear. Initial biomass was estimated from depletion experiments at different
abundance stations by applying the Leslie & Davis (1939) method, modified by Ricker (1975). Each
fishing operation was classified according to its yield (CPUE in g/trap/night). The potential fishing planar
area was estimated between the isobathymetric lines between 90 and 220 m. Total biomasses (Bt) were
calculated from areas (km2) and mean minimum/maximum densities (kg/km2). Maximum sustainable
yield (MSY) was estimated from Bt using the Beddington and Cooke (1983) model by entering natural
mortality (0.6), growth rate (0.53 year�1) and recruitment age (1.32 year), which are the parameters for
this target species published for the Canaries. These parameters estimate a biological exploitation rate
( ) of 0.262. Interpolations were applied to estimate MSY for insular stocks representing lesser than 5%
of the total fishing grounds for this species in the archipelago.
The MSY estimated by depletion were 30.5 tons/year for the stock of SËśao Vicente, Santa Luzia, Ilheus
and SËśao Nicolau, 10 tons/year for the stock of Santiago, 138.8 tons/year for the stock of Boa Vista
and Maio, and 5.6 tons/year for the stock of Sal. The small stocks estimated by interpolation were:
4.5 tons/year for the stock of Santo AntËśao, 1.3 tons/year for the stock of Fogo, and 1.8 tons/year for
the stock of Brava and Ilheus. In total, 192.5 tons per year was the total MSY for the striped soldier
shrimp around the islands of the Cape Verde archipelago, occupying a total area of 1,918 km2 of new
fishing grounds at between 90 and 220 m of depth. In comparison with the traditional bottom trap
used in the Canary Islands, the innovative fishing gear MSFST were proved to be more selective for
pandalid shrimps, minimizing the gear impact on the seafloor as well as the by-catch by reducing the
discards. Depletion methods are based on the assumption of a closed system, that is with minimum or
zero immigration between neighbouring areas. The straight forward decline of CPUEs obtained during
the depletion experiments seems to confirm that P. edwardsii is a low mobility species, making this
assumption valid at least during short-time periods. Because of the bathymetry profile of these islands,the depth range is from very close (few nautical miles in Santiago) to far away (10-12 n.m. in Boa Vista)
to the coastline.
Fishing effort should be controlled on the basis of quotas, number of fishing vessels and a precautionary
approach in order to ensure that catching is commensurate with sustainable levels of exploitation. MSY
estimates suggest that this new Capeverdean fishery should be carried out by specialized medium-sized
fishing vessels. During the last decades a combination of shrimp trawling and industrial trapping activity
has threatened over-exploitation in the Mediterranean fisheries targeting on P. edwardsii; currently the
shrimp collapse has conducted to the decline of these fisheries. Can the Cape Verde regulatory bodies
and all the stakeholders involved learn the lessons this teaches us about this resource management
By-catch composition of the striped soldier shrimp Plesionika edwardsii (Crustace: Decapoda: Pandalidae) experimental fishery in the Cape Verde Islands
This work focuses on the by-catch composition of Plesionika edwardsii experimental fishery in the Cape
Verde Islands. Obtaining information on abundance, composition and lifecycle of species involved in this
potential fishery is useful, in order to ensure its sustainable development under an ecosystem approach.
The first step towards this goal is the description of catches.
Four 15-day research surveys were conducted on board the R/V Prof. Ignacio Lozano: April 2010 (SËśao
Vicente and Santa Luzia islands), November 2011 (Santiago island), March 2012 (Boa Vista island,)
and July 2012 (Sal and SËśao Nicolau islands). The working depths were between 66 and 458 m depth.
A standardized innovative fishing gear was used, so-called multiple semi-floating shrimp traps. Each
fishing line was composed by 40-65 traps operating around 2.4 m above the seafloor, using Decapterus
macarellus (Carangidae) as unique bait of the traps.
Multiple semi-floating shrimp traps is a passive fishing system that allows catch and release sea significant
part of the unwanted catches, as in the case of Chondrichthyes or Anguilliformes, reducing the
fishing impact on non-target species.
The main by-catch was composed of 53 species belonging to three groups including Chondrichthyes
(three families and three species), Crustacea (11 families and 19 species) and Osteichthyes (15 families
and 29 species). Plesionika edwardsii, the target species of this fishery, represented 97.8% of
the catch in terms of abundance and 40.1% in biomass. By-catch represented 59.9% of total catch in
terms of biomass. Osteichthyes (87.5%) were the dominant group and was represented by the following
main families; Sparidae (33.9%), Moridae (32.5%), Muraenidae (32.5%), Scorpaenidae (9.9%) and
Tetraodontidae (9.8%). Chondrichthyes (11.6%) were composed by Centrophoridae (65.3%) and Triakidae
(34.1%). Finally, Crustacea (1.9%) were chiefly composed by Pandalidae (79.1%). However,
different families represented by specific species were found to be dominant around each island. Sparidae
were the dominant family represented by Pagellus acarne (46.2% of total by-catch) at SËśao Vicente,
and by Dentex macrophthalmus (42.6%) at Boa Vista. Tetraodontidae with Sphoeroides pachygaster
(25.9%) and Sparidae with P. acarne (25.1%) were the co-dominant families in the by-catch around
Santa Luzia. Muraenidae were the dominant family represented by Gymnothorax polygonius (69.4%)
at Sal, and by Muraena helena (63.4%) at SËśao Nicolau. Finally, Scorpaenidae with Pontinus kuhlii
(22.3%) and Moridae with Physiculus cyanostrophus (22.1%) were the co-dominant families of the bycatch
around Santiago.
Acknowledgements: This study is part of the PROACTIVA 1-2 (2009-2012) and MARPROF-CV
(2010-2014) projects, in the framework of the Canary Islands Government and UE PCT MAC 2007-
2013 programmes respectively
Simultaneous temperature and humidity measurements in a mechanical ventilator using an optical fibre sensor
An optical fibre sensor for simultaneous temperature and humidity measurements consisting of one fibre Bragg grating (FBG) to measure temperature and a mesoporous film of bilayers of Poly(allylamine hydrochloride)(PAH) and silica (SiO2) nanoparticles deposited onto the tip of the same fibre to measure humidity is reported. The hygroscopic film was created using the layer-by-layer (LbL) method and the optical reflection spectra were measured up to a maximum of 23 bilayers. The temperature sensitivity of the FBG was 10 pm/°C while the sensitivity to humidity was (-1.4x10-12 W / %RH) using 23 bilayers. The developed sensor was tested in the mechanical ventilator and temperature and humidity of the delivered artificial air was simultaneously measured. Once calibrated, the optical fibre sensor has the potential to control the absolute humidity as an essential part of critical respiratory care. © (2016) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only
Estimating the uncertainties of strain and damage analysis by X-ray diffraction in ion implanted MoO3
N/
Tidal torques. A critical review of some techniques
We point out that the MacDonald formula for body-tide torques is valid only
in the zeroth order of e/Q, while its time-average is valid in the first order.
So the formula cannot be used for analysis in higher orders of e/Q. This
necessitates corrections in the theory of tidal despinning and libration
damping.
We prove that when the inclination is low and phase lags are linear in
frequency, the Kaula series is equivalent to a corrected version of the
MacDonald method. The correction to MacDonald's approach would be to set the
phase lag of the integral bulge proportional to the instantaneous frequency.
The equivalence of descriptions gets violated by a nonlinear
frequency-dependence of the lag.
We explain that both the MacDonald- and Darwin-torque-based derivations of
the popular formula for the tidal despinning rate are limited to low
inclinations and to the phase lags being linear in frequency. The
Darwin-torque-based derivation, though, is general enough to accommodate both a
finite inclination and the actual rheology.
Although rheologies with Q scaling as the frequency to a positive power make
the torque diverge at a zero frequency, this reveals not the impossible nature
of the rheology, but a flaw in mathematics, i.e., a common misassumption that
damping merely provides lags to the terms of the Fourier series for the tidal
potential. A hydrodynamical treatment (Darwin 1879) had demonstrated that the
magnitudes of the terms, too, get changed. Reinstating of this detail tames the
infinities and rehabilitates the "impossible" scaling law (which happens to be
the actual law the terrestrial planets obey at low frequencies).Comment: arXiv admin note: sections 4 and 9 of this paper contain substantial
text overlap with arXiv:0712.105
The fish family Muraenidae: an ideal group for testing at small-scale the coherency of Macaronesia as a biogeographic unit, with the first report on separate fishery statistics
: The present study was conceptualized to study the muraenid species (moray eels) occurring around the volcanic archipelagos of the Azores, Madeira, Selvagens, Canary and Cabo Verde islands (eastern-central Atlantic). The biogeographic patterns of these species were analysed and compared. We then hypothesized that this fish family is an ideal group
for testing at small-scale the coherency of Macaronesia and its direct biogeographic units: i.e. the Azores, Webbnesia and
Cabo Verde, as proposed in recent scientific literature. Additionally, this paper provides for the first time separate fishery
statistics for this group in the region that were analysed to contrast the biogeographic results.En prensa1,00
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