366 research outputs found
Pesquisa de agentes entomopatogénicos na Ilha Terceira (Açores).
IX Expedição Científica do Departamento de Biologia - Terceira 1994.Durante a "Expedição Científica Terceira 1994" fez-se a recolha de amostras de solo para pesquisa de nemátodos e fungos entomopatogénicos no âmbito do projecto de colecção e caracterização da variabilidade genética de agentes entomopatogénicos nos Açores. Com o designado "Galleria trap
method" isolaram-se 4 nemátodos do género Heterorhabditis, todos morfologicamente próximos de Heterorhabditis bacteriophora, e 1 fungo, identificado como Beauveria bassiana
Structure assignment of seized products containing cathinone derivatives using high resolution analytical techniques
The innovation of the new psychoactive substances (NPS) market requires the rapid identification of new substances that can be a risk to public health, in order to reduce the damage from their use. Twelve seized products suspected to contain illicit substances were analyzed by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), gas chromatography coupled to mass spectrometry (GC-MS), and nuclear magnetic resonance spectroscopy (NMR). Synthetic cathinones (SCat) were found in all products, either as a single component or in mixtures. Infrared spectra of all products were consistent with the molecular structure of SCat, showing an intense absorption band at 1700-1674 cm-1, corresponding to the carbonyl stretching, a medium/strong peak at 1605-1580 cm-1, indicating stretching vibrations in the aromatic ring (C=C) and bands with relative low intensity at frequencies near 2700-2400 cm-1, corresponding to an amine salt. It was possible to identify a total of eight cathinone derivatives by GC-MS and NMR analysis: 4'-methyl-α-pyrrolidinohexanophenone (MPHP), α-pyrrolidinohexanophenone (α-PHP), 3-fluoromethcathinone (3-FMC), methedrone, methylone, buphedrone, N-ethylcathinone, and pentedrone. Among the adulterants found in these samples, caffeine was the most frequently detected substance, followed by ethylphenidate. These results highlight the prevalence of SCat in seized materials of the Portuguese market. Reference standards are usually required for confirmation, but when reference materials are not available, the combination of complementary techniques is fundamental for a rapid and an unequivocal identification of such substances.info:eu-repo/semantics/publishedVersio
Acoustic determination of thermophysical properties and critical parameters for R404A and critical line of x CO2+(1− x) R404A
The thermophysical properties and critical parameters for the alternative refrigerant R404A (52 wt % of 1,1,1-
trifluoroethane (R143a) + 44 wt % of pentafluoroethane (R125) + 4 wt % of 1,1,1,2-tetrafluoroethane (R134a))
were investigated using two different acoustic techniques. The critical behavior of the system xCO2 +
(1 - x)R404A was also investigated. Experimental data of speed of sound in liquid R404A from 258 K to
338 K and pressures up to 65 MPa were measured using a pulse-echo method. Derived thermodynamic properties
are calculated, combining our experimental data with density and isobaric heat capacity values published by
other authors. Measurements of the critical temperature Tc and pressure pc on (R404A) and mixtures of xCO2 +
(1 - x)R404A were performed using another simple ultrasonic time-delay technique. The binary critical line was
determined over the whole composition range showing that this system deviates only slightly from ideality since
the critical line is a continuous line. The Peng-Robinson equation of state with conventional mixing and combining
rules was used to correlate the binary experimental data.info:eu-repo/semantics/publishedVersio
Acoustic determination of thermophysical properties and critical parameters for R410A and critical line of x CO2+(1− x) R410A
The thermophysical properties and critical parameters for the alternative refrigerant R410A (a near azeotropic
refrigerant mixture containing difluoromethane (R32) and pentafluoroethane (R125) (50 wt % of each)) were
investigated using two different acoustic techniques. The critical behavior of the system xCO2 + (1 - x)R410A
was also investigated. Experimental data of speed of sound in liquid R410A from (253 to 338) K and pressures
up to 65 MPa were measured using a pulse-echo method. Derived thermodynamic properties were calculated,
combining our experimental data with density and isobaric heat capacity values published by other authors.
Measurements of the critical temperature Tc and pressure pc on (R410A) and mixtures of xCO2 + (1 - x)R410A
were performed using another simple ultrasonic time-delay technique. The binary critical line was determined
over the whole composition range, showing that this system deviates only slightly from ideality since the critical
line is a continuous line. The Peng-Robinson equation of state with conventional mixing and combining rules
was used to correlate the binary experimental data.info:eu-repo/semantics/publishedVersio
Dust-filled axially symmetric universes with a cosmological constant
Following the recent recognition of a positive value for the vacuum energy
density and the realization that a simple Kantowski-Sachs model might fit the
classical tests of cosmology, we study the qualitative behavior of three
anisotropic and homogeneous models: Kantowski-Sachs, Bianchi type-I and Bianchi
type-III universes, with dust and a cosmological constant, in order to find out
which are physically permitted. We find that these models undergo
isotropization up to the point that the observations will not be able to
distinguish between them and the standard model, except for the Kantowski-Sachs
model
with smaller than some critical value
. Even if one imposes that the Universe should be nearly
isotropic since the last scattering epoch (), meaning that the
Universe should have approximately the same Hubble parameter in all directions
(considering the COBE 4-Year data), there is still a large range for the matter
density parameter compatible with Kantowsky-Sachs and Bianchi type-III if
, for a very small . The
Bianchi type-I model becomes exactly isotropic owing to our restrictions and we
have in this case. Of course, all these models
approach locally an exponential expanding state provided the cosmological
constant .Comment: 12 pages, 9 figures, 1 table. Published in Physical Review D 1
In situ measurement of hydraulic conductivity of mountain soils: a case study in Serra da Estrela mountain (Central Portugal)
Understanding the role of the vadose zone is essential to accurately assess hydrogeological systems
and the respective groundwater resources. The study area (Manteigas – Nave de Santo António – Torre
sector, Serra da Estrela Mountain, Central Portugal) presents specific geological, morphotectonical
and climatic characteristics with significant influence on the hydrogeologic regime. The vadose zone has particular features that contribute to control both the quantity and the quality of the
groundwater resources. In situ hydraulic conductivity tests were carried out in A and H soil horizons,
by means of the constant head permeameter (Guelph permeameter) method. The mean value of the
field saturated hydraulic conductivity is high (around 6 cm/h) and is typical of coarse textured soils.
Unsaturated hydraulic conductivity was estimated using the Gardner mathematical model
A methodological approach to potential vegetation modeling using GIS techniques and phytosociological expert-knowledge: application to mainland Portugal
An attempt to obtain a consistent spatial model of natural potential vegetation
(NPV) for the mainland Portuguese territory is reported. Spatial modeling procedures
performed in a Geographic Information System (GIS) environment, aimed to operationalize
phytosociological expert-knowledge about the putative distribution of potential zona1
forest communities dominam in the Portuguese continental territories. The paradigm for
NPV assumed was that of RIVAS-MARTINE(1Z9 76) and RIVAS-MARTINEeZt al. (1999),
which presupposes, for a given territory, a univocal correspondence between a uniform
combination of bioclimatic stage and lithology' gi ven a biogeographical context, and a
unique successional sequence leading to a single climax community (i. e. a vegetation series
(VS)). Information issued from both literature and a team of phytosociologists possessing
detailed knowledge about Portuguese vegetation, namely about forests and its seria1 vegetation,
was acknowledged as a starting point for the construction of such a habitat-vegetation
correspondence model. First, a bioclimatic map concerning the "Worldwide Bioclimatic
Classification System" (WBCS) of RIVAS-MARTINE(1Z9 81 -2004), obtained by multivariate
grostatistical interpolation issuing from the work of MESQUITA(2 005), was set.
Severa1 partia1 matrices, one for each biogeographical Province, combined such habitat
statements to VS. Initial incoherence due to vagueness of statements led to an important
amount of both superimposition of VS and habitat gaps in the matrices. Further rearrangement
of the table according to known field distribution of VS by experts allowed
setting an approximate univocal correspondence VS-habitat. Finally, an intersection of
bioclimatic, lithology and biogeographic maps yielded over a thousand habitat combinations
to be associated each to a single VS through implementation of the matrices as a set
of rules. Again, inconsistencies were solved likewise, but this time by direct observation
of the map by experts. Keeping of phytosociological consistency and fidelity to information
on actual vegetation field distribution was always mandatory during the proces
Effects of grass silage and soybean meal supplementation on milk production and milk fatty acid profiles of grazing dairy cows
Copyright © American Dairy Science Association, 2008.The effects of supplementation with grass silage and replacement of some corn in the concentrate with soybean meal (SBM) on milk production, and milk fatty acid (FA) profiles were evaluated in a replicated 4 × 4 Latin square study using 16 dairy cows grazing pasture composed of ryegrass, Kentucky bluegrass, and white clover. Each experimental period lasted for 3 wk. The 4 dietary treatments were PC, 20 h of access to grazing pasture, supplemented with 6 kg/d of corn-based concentrate mixture (96% corn; C); PCSB, 20 h of access to grazing pasture, supplemented with 6 kg/d of corn- and SBM-based concentrate mixture (78% corn and 18% SBM; CSB); SC, 7 h of access to grazing pasture during the day and 13 h of ad libitum access to grass silage at night, supplemented with 6 kg/d of C concentrate; and SCSB, 7 h of access to grazing pasture during the day and 13 h of ad libitum access to grass silage at night, supplemented with 6 kg/d of CSB concentrate. The concentrate mixtures were offered twice each day in the milking parlor and were consumed completely. Grass silage supplementation reduced dietary crude protein and concentration of total sugars, and dietary SBM inclusion increased dietary crude protein concentration and decreased dietary starch concentration. Milk yield and energy-corrected milk were increased by SBM supplementation of cows with access to grass silage. Milk protein concentration was lower in cows offered grass silage, regardless of whether SBM was fed. Dietary SBM inclusion tended to increase milk fat concentration. Plasma urea N was reduced by silage feeding and increased by SBM supplementation. Supplementation with grass silage overnight could represent a useful strategy for periods of lower pasture availability. Dietary inclusion of SBM in solely grazing cows had no effects on milk production and composition, exacerbated the inefficient capture of dietary N, and increased diet cost. Grass silage supplementation affected milk FA profiles, increasing both the FA derived from de novo synthesis and those derived from rumen microbial biomass, and decreasing the sum of C18 FA (mostly derived from diet or from mobilization of adipose tissue reserves). Milk fat concentrations of conjugated linoleic acid cis-9, trans-11, vaccenic acid (18:1 trans-11), and linolenic acid (18:3n-3) were unaffected by grass silage supplementation, suggesting that partial replacement of pasture by unwilted grass silage does not compromise the dietary quality of milk fat for humans
ICN as Network Infrastructure for Multi-Sensory Devices: Local Domain Service Discovery for ICN-based IoT Environments
Information Centric Networking (ICN) is an emerging research topic aiming at shifting the Internet from its current host-centric paradigm towards an approach centred around content, which enables the direct retrieval of information objects in a secure, reliable, scalable, and efficient way. The exposure of ICN to scenarios other than static content distribution is a growing research topic, promising to extend the impact of ICN to a broader scale. In this context, particular attention has been given to the application of ICN in Internet of Things (IoT) environments. The current paper, by focusing on local domain IoT scenarios, such as multi-sensory Machine to Machine environments, discusses the challenges that ICN, particularly Interest-based solutions, impose to service discovery. This work proposes a service discovery mechanism for such scenarios, relying on an alternative forwarding pipeline for supporting its core operations. The proposed mechanism is validated through a proof-of-concept prototype, developed on top of the Named Data Networking ICN architecture, with results showcasing the benefits of our solution for discovering services within a collision domain. © 2017 Springer Science+Business Media New Yor
Técnica do Inseto Estéril (TIE): nova tecnologia para o controle de moscas-das-frutas no Brasil; Projeto Piloto Livramento de Nossa Senhora.
Neste trabalho, relatam-se os resultados do “Projeto Piloto para Uso de Moscamed Estéril em Livramento de Nossa Senhora”, no Sudoeste da Bahia. O projeto teve como objetivo testar a efi ciência da linhagem “Viena 8” de C. capitata, nas condições do semi-árido do Nordeste do Brasil, bem como a logística de transporte e de liberação massal em campo, como uma ação pró-ativa às atividades da Bio-fábrica Moscamed Brasil
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