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Mechanical Properties of Pure Titanium Models Processed by Selective Laser Melting
The influence of laser processing parameters on mechanical properties and microstructure
of pure titanium models made by selective laser melting is investigated. The density of the
models can reach higher than 95% under proper conditions. Although the tensile strength test
shows results comparable to the wrought material, the impact and torsional fatigue strengths are
low because of porosity and oxygen pick-up suggested by increasing of hardness. Hot isostatic
pressing allows almost full densification and greatly improves mechanical properties.Mechanical Engineerin
Study of a simplified model for DFIG-based wind turbines
In the study of the dynamical behavior of doublyfed
induction generators (DFIG), for wind power applications,
the use of reduced order models is useful in order to design
specific control strategies for wind power plants as well as to
obtain lightweight computing simulations. Within this field this
paper presents a new dynamic model for wind turbines, based
on DFIG, able of representing accurately its behavior during
both the steady state and the transient of the grid voltage. As it
will be proven this model permits to perform an accurate
analysis of the system when there is a voltage dip in the grid. In
the following a theoretical study of this model will be carried out
and the accuracy of its performance will be tested under
different conditions, by means of PSCAD/EMTDC simulations,
in order to show its reliability. Finally the reliability of the
simplified model will be tested in a scaled experimental setup.Peer ReviewedPostprint (published version
On the statistical and transport properties of a non-dissipative Fermi-Ulam model
The transport and diffusion properties for the velocity of a Fermi-Ulam model were characterized using the decay rate of the survival probability. The system consists of an ensemble of non-interacting particles confined to move along and experience elastic collisions with two infinitely heavy walls. One is fixed, working as a returning mechanism of the colliding particles, while the other one moves periodically in time. The diffusion equation is solved, and the diffusion coefficient is numerically estimated by means of the averaged square velocity. Our results show remarkably good agreement of the theory and simulation for the chaotic sea below the first elliptic island in the phase space. From the decay rates of the survival probability, we obtained transport properties that can be extended to other nonlinear mappings, as well to billiard problems.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES
Bayesian hierarchical modelling approaches for combining information from multiple data sources to produce annual estimates of national immunization coverage
Estimates of national immunization coverage are crucial for guiding policy
and decision-making in national immunization programs and setting the global
immunization agenda. WHO and UNICEF estimates of national immunization coverage
(WUENIC) are produced annually for various vaccine-dose combinations and all
WHO Member States using information from multiple data sources and a
deterministic computational logic approach. This approach, however, is
incapable of characterizing the uncertainties inherent in coverage measurement
and estimation. It also provides no statistically principled way of exploiting
and accounting for the interdependence in immunization coverage data collected
for multiple vaccines, countries and time points. Here, we develop Bayesian
hierarchical modeling approaches for producing accurate estimates of national
immunization coverage and their associated uncertainties. We propose and
explore two candidate models: a balanced data single likelihood (BDSL) model
and an irregular data multiple likelihood (IDML) model, both of which differ in
their handling of missing data and characterization of the uncertainties
associated with the multiple input data sources. We provide a simulation study
that demonstrates a high degree of accuracy of the estimates produced by the
proposed models, and which also shows that the IDML model is the better model.
We apply the methodology to produce coverage estimates for select vaccine-dose
combinations for the period 2000-2019. A contributed R package {\tt imcover}
implementing the No-U-Turn Sampler (NUTS) in the Stan programming language
enhances the utility and reproducibility of the methodology.Comment: 31 pages (main), 4 figure
'Chardonel' Grape
'Chardonel' resulted from the cross, 'SeyvaT x 'Chardonnay,'
made in 1953. Fruit were first observed in 1958, and the
original vine was propagated in 1960 under the number NY
45010. In later testing, it was re-named GW 9 (Geneva White 9)
for ease of identification in cooperatively run yield trials. The
vine was initially described as vigorous and productive with
large clusters
Antiplasmodial Properties and Cytotoxicity of Endophytic Fungi from Symphonia globulifera (Clusiaceae)
Ateba JET, Toghueo RMK, Awantu AF, et al. Antiplasmodial Properties and Cytotoxicity of Endophytic Fungi from Symphonia globulifera (Clusiaceae). JOURNAL OF FUNGI. 2018;4(2): UNSP 70.There is continuing need for new and improved drugs to tackle malaria, which remains a major public health problem, especially in tropical and subtropical regions of the world. Natural products represent credible sources of new antiplasmodial agents for antimalarial drug development. Endophytes that widely colonize healthy tissues of plants have been shown to synthesize a great variety of secondary metabolites that might possess antiplasmodial benefits. The present study was carried out to evaluate the antiplasmodial potential of extracts from endophytic fungi isolated from Symphonia globulifera against a chloroquine-resistant strain of Plasmodium falciparum (PfINDO). Sixty-one fungal isolates with infection frequency of 67.77% were obtained from the bark of S. globulifera. Twelve selected isolates were classified into six different genera including Fusarium, Paecilomyces, Penicillium, Aspergillus, Mucor, and Bipolaris. Extracts from the 12 isolates were tested against PfINDO, and nine showed good activity (IC50 < 10 mu g.mL(-1)) with three fungi including Paecilomyces lilacinus (IC50 = 0.44 mu g.mL(-1)), Penicillium janthinellum (IC50 = 0.2 mu g.mL(-1)), and Paecilomyces sp. (IC50 = 0.55 mu g.mL(-1)) showing the highest promise. These three isolates were found to be less cytotoxic against the HEK293T cell line with selectivity indices ranging from 24.52 to 70.56. Results from this study indicate that endophytic fungi from Symphonia globulifera are promising sources of hit compounds that might be further investigated as novel drugs against malaria. The chemical investigation of active extracts is ongoing
Re-evaluation of manganese solubility as affected by soil sample preparation in the laboratory
Intergroup conflict management strategies from a nobel peace laureate: The case of Jose Ramos-Horta
We report on the case of Dr. José Ramos-Horta (JRH), a 1996 Nobel Peace Laureate, former President of East Timor, and current envoy of the United Nations to Guinea-Bissau. JRH agreed to an interview detailing the peace building strategies he has used to manage conflicts. The transcript of his Nobel Laureate acceptance speech was also analysed to strengthen the overall narrative. Our findings suggest two higher-order themes: (1) psycho-social skills, and (2) social networking. Specifically, JRH uses active listening, mindful breaks, and awareness of media trends to create personal and strategic networking contacts, which are critical elements in managing conflict
Measurements of fiducial and differential cross sections for Higgs boson production in the diphoton decay channel at s√=8 TeV with ATLAS
Measurements of fiducial and differential cross sections are presented for Higgs boson production in proton-proton collisions at a centre-of-mass energy of s√=8 TeV. The analysis is performed in the H → γγ decay channel using 20.3 fb−1 of data recorded by the ATLAS experiment at the CERN Large Hadron Collider. The signal is extracted using a fit to the diphoton invariant mass spectrum assuming that the width of the resonance is much smaller than the experimental resolution. The signal yields are corrected for the effects of detector inefficiency and resolution. The pp → H → γγ fiducial cross section is measured to be 43.2 ±9.4(stat.) − 2.9 + 3.2 (syst.) ±1.2(lumi)fb for a Higgs boson of mass 125.4GeV decaying to two isolated photons that have transverse momentum greater than 35% and 25% of the diphoton invariant mass and each with absolute pseudorapidity less than 2.37. Four additional fiducial cross sections and two cross-section limits are presented in phase space regions that test the theoretical modelling of different Higgs boson production mechanisms, or are sensitive to physics beyond the Standard Model. Differential cross sections are also presented, as a function of variables related to the diphoton kinematics and the jet activity produced in the Higgs boson events. The observed spectra are statistically limited but broadly in line with the theoretical expectations
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