306 research outputs found
Development of a qualitative PCR method for the Alexandrium (Dinophyceae) detection in contaminated mussels (Mytilus galloprovincialis)
Paralytic shellfish poisoning (PSP) is a syndrome caused by the consumption of shellfish contaminated with neurotoxins
produced by organisms of themarine dinoflagellate genus Alexandrium. A. minutum is the mostwidespread species responsible for PSP in theWestern Mediterranean basin. The standard monitoring of shellfish farms for the presence of harmful algae and related toxins usually requires the microscopic examination of phytoplankton populations, bioassays and toxin determination by HPLC. These procedures are time-consuming and require remarkable experience, thus limiting the number of specimens that can be analyzed by a single laboratory unit.Molecular biology techniques may be helpful in the detection of target microorganisms in field samples. In this study, we developed a qualitative PCR assay for the rapid detection of all potentially toxic species belonging to the Alexandrium genus and specifically A. minutum, in contaminated mussels. Alexandrium genus-specific primers were designed to target the 5.8S rDNA region, while an A. minutum species-specific primer was designed to bind in the ITS1 region. The assay was validated using several fixed seawater samples fromthe Mediterranean basin, which were analyzed using PCR along with standard microscopy procedures. The assay provided a rapid method for monitoring the presence of Alexandrium spp. in mussel tissues, as well as in seawater samples. The results showed that PCR is a valid, rapid alternative procedure for the detection of target phytoplankton species either in seawater or directly in mussels, where microalgae can accumulat
Fabrication and Results of the First MgB2 Round Coil Superferric Magnet at LASA
The LASA Laboratory (INFN, Milan) is working in the High Luminosity LHC program to develop, in collaboration with CERN, six different types of High Order corrector magnets. In this framework, in parallel with a conventional design of superferric magnets with LTS conductor, the LASA is focusing on the research of new superconducting materials which may have applications in particle accelerator magnets. To this purpose, LASA is developing a new type of superferric magnet suitable to arbitrary multipole order, called Round Coil Superferric Magnets (RCSM). The iron yoke shaped with an arbitrary number of poles is able to create the desired harmonic component using only one single round coil with a large bending radius suitable for very strain-sensitive superconductors. The electromagnetic design of a sextupole configuration of the magnet and the production of the first superconducting MgB2 round coil prototype have been already presented. In this paper, we expose the optimization of the iron yoke and polar expansions assembly of the first magnet semi-module prototype. The results of the whole powering test are described in detail and the analysis of the magnetic performances are compared with those of classical superferric correctors
Giant and tunable anisotropy of nanoscale friction in graphene
CNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPERJ - FUNDAÇÃO CARLOS CHAGAS FILHO DE AMPARO À PESQUISA DO ESTADO DO RIO DE JANEIROFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOFAPEMIG - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE MINAS GERAISThe nanoscale friction between an atomic force microscopy tip and graphene is investigated using friction force microscopy (FFM). During the tip movement, friction forces are observed to increase and then saturate in a highly anisotropic manner. As a result, the friction forces in graphene are highly dependent on the scanning direction: under some conditions, the energy dissipated along the armchair direction can be 80% higher than along the zigzag direction. In comparison, for highly-oriented pyrolitic graphite (HOPG), the friction anisotropy between armchair and zigzag directions is only 15%. This giant friction anisotropy in graphene results from anisotropies in the amplitudes of flexural deformations of the graphene sheet driven by the tip movement, not present in HOPG. The effect can be seen as a novel manifestation of the classical phenomenon of Euler buckling at the nanoscale, which provides the non-linear ingredients that amplify friction anisotropy. Simulations based on a novel version of the 2D Tomlinson model (modified to include the effects of flexural deformations), as well as fully atomistic molecular dynamics simulations and first-principles density-functional theory (DFT) calculations, are able to reproduce and explain the experimental observations.The nanoscale friction between an atomic force microscopy tip and graphene is investigated using friction force microscopy (FFM). During the tip movement, friction forces are observed to increase and then saturate in a highly anisotropic manner. As a result, the friction forces in graphene are highly dependent on the scanning direction: under some conditions, the energy dissipated along the armchair direction can be 80% higher than along the zigzag direction. In comparison, for highly-oriented pyrolitic graphite (HOPG), the friction anisotropy between armchair and zigzag directions is only 15%. This giant friction anisotropy in graphene results from anisotropies in the amplitudes of flexural deformations of the graphene sheet driven by the tip movement, not present in HOPG. The effect can be seen as a novel manifestation of the classical phenomenon of Euler buckling at the nanoscale, which provides the non-linear ingredients that amplify friction anisotropy. Simulations based on a novel version of the 2D Tomlinson model (modified to include the effects of flexural deformations), as well as fully atomistic molecular dynamics simulations and first-principles density-functional theory (DFT) calculations, are able to reproduce and explain the experimental observations.619CNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPERJ - FUNDAÇÃO CARLOS CHAGAS FILHO DE AMPARO À PESQUISA DO ESTADO DO RIO DE JANEIROFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOFAPEMIG - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE MINAS GERAISCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPERJ - FUNDAÇÃO CARLOS CHAGAS FILHO DE AMPARO À PESQUISA DO ESTADO DO RIO DE JANEIROFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOFAPEMIG - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE MINAS GERAISSem informaçãoSem informação2013/08293-7, 2014/15521-9Sem informaçãoAll authors aknowledge the financial support from Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) and Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ). R.P. acknowledges Fundação de Amparo a Pesquisa do Estado de São Paulo (Fapesp) for financial support through Grant #2014/15521-9. D.S.G. thanks the Center for Computational Engineering and Sciences at Unicamp for financial support through the FAPESP/CEPID Grant # 2013/08293-7. Computer simulations carried out during this research were supported by resources supplied by the Center for Scientific Computing (NCC/GridUNESP) of the São Paulo State University (UNESP). L.G.C. acknowledges FAPEMIG and the grant PRONAMETRO (52600.056330/2012). B.F acknowledges FAPEMIG and the grant PRONAMETRO (52600.030929/2014)
DIVERSIDAD DE LOS NEMATODOS DE TETRA COLA ROJA ASTYANAX AFF. PARANAE (TELEOSTEI: CHARACIDAE) DE SITIOS CONTAMINADOS DE UN SISTEMA DE RÍO TROPICAL
Aquatic systems are affected by a great variety of anthropogenic activities that alter the water quality through the introduction of organic and inorganic pollutants, consequently impacting all trophic levels of a biological community. The relationship between parasite species diversity and organic pollution in the high Paraná River basin, Paraná, Brazil was investigated during two seasons (Winter and Summer) of 2011. A total of 114 red-tail-lambari (Astyanax aff. paranae Eigenmann, 1914) were sampled from a non-impacted location (Perobas Reserve) and from impacted regions (agricultural and urban regions, upstream and downstream the city of Campo Mourão, respectively). The nematode Spinitectus yorkei Travassos, Artigas & Pereira, 1928 was found on the preserved area, while the nematode Procamallanus (Spirocamallanus) inopinatus Travassos, Artigas & Pereira, 1928 was found only on the severely polluted areas. The variability of the prevalence index suggests that the structure of the parasite community is affected at different ways by the same levels of pollutants on the water. The observed results assume that the alteration in parasite diversity can be related to increased organic pollution, and that the differences in the parasite community from different environments can be related to biotic stress.Los sistemas acuáticos se ven afectados por una gran variedad de actividades antropogénicas que alteran la calidad del agua a través de la introducción de contaminantes orgánicos e inorgánicos, por consiguiente, afectan a todos los niveles de la comunidad biológica. De esta forma, la relación entre la diversidad de especies de parásitos y la contaminación orgánica en la cuenca del alto Paraná, Paraná, Brasil, se investigó en dos temporadas (invierno y verano) de 2011. Un total de 114 tetra cola roja (Astyanax aff. paranae Eigenmann, 1914) se muestrearon en un sitio no impactado (Reserva Perobas) y en regiones impactadas (zonas agrícolas y urbanas, aguas arriba y aguas abajo de la ciudad de Campo Mourão, respectivamente). El nematodo Spinitectus yorkei Travassos, Artigas y Pereira, 1928 se encuentran en la zona protegida, mientras que el nematodo Procamallanus (Spirocamallanus) inopinatus Travassos, Artigas y Pereira, 1928 se encuentran sólo en las zonas gravemente contaminadas. La variabilidad del índice de prevalencia sugiere que la estructura de la comunidad de parásitos se ve afectada en diferentes formas por el mismo nivel de contaminantes en el agua. Los resultados observados asumen que la alteración en la diversidad parasitaria puede estar relacionada con el aumento de la contaminación orgánica, y que la respuesta de la comunidad de parásitos a las tensiones ambientales puede ser utilizada como bioindicadora
Post hoc depression analysis from a pharmacist-led diabetes trial
Introduction: Diabetes and depression may present concurrently, and clinical pharmacists are well equipped to manage these conditions. Clinical pharmacists were grant funded to implement a diabetes-focused randomized controlled trial in a Federally Qualified Health Center. The objective of this analysis is to evaluate if glycemic control and depressive symptoms improve for patients with diabetes and depression with additional management from clinical pharmacists compared with those receiving the standard of care.
Methods: This is a post hoc subgroup analysis of a diabetes-focused randomized controlled trial. Pharmacists enrolled patients with type 2 diabetes mellitus (T2DM) and a glycated hemoglobin (A1C) greater than 8% and randomly assigned them to 1 of 2 cohorts, one managed by the primary care provider alone and one with additional care from the pharmacist. Pharmacists completed encounters with patients who have T2DM with or without depression to comprehensively optimize pharmacotherapy while tracking glycemic and depressive outcomes throughout the study.
Results: A1C improved from baseline to 6 months in patients with depressive symptoms who received additional care from pharmacists by -2.4 percentage points (SD, 2.41) compared with a -0.1 percentage point (SD, 1.78) reduction in the control arm (P .0081), and there was no change in depressive symptoms.
Discussion: Patients with T2DM and depressive symptoms experienced better diabetes outcomes with additional pharmacist management compared with a similar cohort of patients with depressive symptoms, managed independently by primary care providers. These patients with diabetes and comorbid depression received a higher level of engagement and care from the pharmacists, which led to more therapeutic interventions
Nanostructured Europium Oxide thin films deposited by pulsed laser ablation of a metallic target in a He buffer atmosphere
Nanostrucured Europium oxide and hydroxide films were obtained by pulsed
Nd:Yag (532 nm) laser ablation of an Europium metallic target, in the presence
of a 1 mbar Helium buffer atmosphere. Both the produced film and the ambient
plasma were characterized. The plasma was monitored by an electrostatic probe,
for plume expansion in vacuum or in the presence of the buffer atmosphere. The
time evolution of the ion saturation current was obtained for several probe to
substrate distances. The results show the splitting of the plume into two
velocity groups, being the lower velocity profile associated with metal cluster
formation within the plume. The films were obtained in the presence of helium
atmosphere, for several target to substrate distances. They were analyzed by
Rutherford backscattering spectrometry (RBS), X-Ray Diffraction (XRD) and
Atomic Force Microscopy, for samples as-deposited and treated at 600 degrees C
in air. The results show that the as-deposited samples are amorphous and have
chemical composition compatible with Europium hydroxide. The thermally treated
samples show X-Ray diffraction peaks of Eu_2O_3, with chemical composition
showing excess oxygen. Film nanostructuring was shown to be strongly correlated
to cluster formation, as shown by velocity splitting in probe current versus
time plots.Comment: 7 pages, 11 figures, 31 reference
Analysis of short-circuit transients in the LHC main dipole circuit
After the occurrence and detection of a short circuit to ground in the LHC main dipole circuit, a fast power abort is triggered and the current in the circuit starts decaying semi-exponentially from a maximum value of 11.85 kA to zero, with a time constant of 103 s. If a short to ground occurs, the current flows through the fuse that is present in the grounding subcircuit. Depending on the value of the thermal load, the fuse first enters a pre-arcing region where it starts intermittently blowing up, until the blow-up threshold is reached, after which it definitively blows up. A simulation scheme utilising a common interface between PSpice and Matlab is proposed in order to simulate the blow-up behaviour of the fuse and hence increase the accuracy of the circuit model for short circuits to ground. A parametric analysis of the short circuit to ground parameters is performed and a better understanding of the behaviour of the circuit under different conditions is obtained. The worst-case values of the voltage to ground in the LHC main dipole circuit are identified for both the case where the intermittent behaviour of the fuse is included in the model as well as for the case where the fuse is not modelled and a comparison between the two is given
A Work Proposal for a Collaborative Study of Magnet Technology for a Future Muon Collider
In this paper we elaborate on the nature and challenges for the magnet
systems of a muon collider as presently considered within the scope of the
International Muon Collider Collaboration (IMCC). We outline the structure of
the work proposed over the coming period of five years to study and demonstrate
relevant magnet technology. The proposal, which is part of the overall work
planned to establish feasibility of a muon collider, is in direct response to
the recent recommendations received from the Laboratories Directors Group
(LDG). The plan is to profit from joint activities, within the scope of the
IMCC and beyond, implemented through direct and EU-funded contributions.Comment: contribution to Snowmass 202
A Muon Collider Facility for Physics Discovery
Muon colliders provide a unique route to deliver high energy collisions thatenable discovery searches and precision measurements to extend ourunderstanding of the fundamental laws of physics. The muon collider design aimsto deliver physics reach at the highest energies with costs, power consumptionand on a time scale that may prove favorable relative to other proposedfacilities. In this context, a new international collaboration has formed tofurther extend the design concepts and performance studies of such a machine.This effort is focused on delivering the elements of a 10 TeV center ofmass (CM) energy design to explore the physics energy frontier. The path tosuch a machine may pass through lower energy options. Currently a 3 TeV CMstage is considered. Other energy stages could also be explored, e.g. ans-channel Higgs Factory operating at 125 GeV CM. We describe the status of theR&D and design effort towards such a machine and lay out a plan to bring theseconcepts to maturity as a tool for the high energy physics community.<br
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