143 research outputs found
Precision Measurement of 11Li moments: Influence of Halo Neutrons on the 9Li Core
The electric quadrupole moment and the magnetic moment of the 11Li halo
nucleus have been measured with more than an order of magnitude higher
precision than before, |Q| = 33.3(5)mb and mu=3.6712(3)mu_N, revealing a
8.8(1.5)% increase of the quadrupole moment relative to that of 9Li. This
result is compared to various models that aim at describing the halo
properties. In the shell model an increased quadrupole moment points to a
significant occupation of the 1d orbits, whereas in a simple halo picture this
can be explained by relating the quadrupole moments of the proton distribution
to the charge radii. Advanced models so far fail to reproduce simultaneously
the trends observed in the radii and quadrupole moments of the lithium
isotopes.Comment: 4 pages, 4 figures, 1 tabl
Magnetic Moment of the Fragmentation Aligned 61Fe(9/2)+ Isomer
We report on the g factor measurement of the isomer in (). The isomer was produced and spin-aligned via a projectile-fragmentation
reaction at intermediate energy, the Time Dependent Perturbed Angular
Distribution (TDPAD) method being used for the measurement of the g factor. For
the first time, due to significant improvements of the experimental technique,
an appreciable residual alignment of the isomer has been observed, allowing a
precise determination of its g factor: . Comparison of the
experimental g factor with shell-model and mean field calculations confirms the
spin and parity assignments and suggests the onset of deformation due
to the intrusion of Nilsson orbitals emerging from the .Comment: 4 figures. Submitted to Phys. Rev. Let
Efecto del antígeno excretor-secretor de leishmania braziliensis sobre la fagocitosis en macrófagos.
Leishmania braziliensis es un flagelado digénico que causa patología en mamíferos.El insecto vector inocula formas promastigotes del parásito en el torrente circulatorio delhospedador. Los parásitos deben ser endocitados rápidamente por los macrófagos u otrosfagocitos, en los que se reproduce como amastigote dentro de una vacuola parasitófora; lospromastigotes que no son internalizados mueren. Se sabe que la activación de los macrófagos, pormoléculas como los lipopolisacáridos (LPS) por ejemplo, producen mediadores químicos queregulan la respuesta inmune humoral y determinan la producción de interleuquinas Th1 o Th2, perose desconoce el efecto de la activación de los macrófagos sobre el proceso de fagocitosis. Por otraparte, se ha visto que el antígeno excretor-secretor producido por promastigotes (AESPL) de L.donovani activa a macrófagos murinos para la producción de interleuquinas pero no se conoce suefecto sobre el proceso de fagocitosis
Analysis and design of wideband distributed VCOs based on switched-cells tuning technique
Two naphthalene degrading bacteria belonging to the genera Paenibacillus and Pseudomonas isolated from a highly polluted lagoon perform different sensitivities to the organic and heavy metal contaminants
Two bacterial strains were isolated in the presence of naphthalene as the sole carbon and energy source from sediments of the Orbetello Lagoon, Italy, which is highly contaminated with both organic compounds and metals. 16S rRNA gene sequence analysis of the two isolates assigned the strains to the genera Paenibacillus and Pseudomonas. The effect of different contaminants on the growth behaviors of the two strains was investigated. Pseudomonas sp. ORNaP2 showed a higher tolerance to benzene, toluene, and ethylbenzene than Paenibacillus sp. ORNaP1. In addition, the toxicity of heavy metals potentially present as co-pollutants in the investigated site was tested. Here, strain Paenibacillus sp. ORNaP1 showed a higher tolerance towards arsenic, cadmium, and lead, whereas it was far more sensitive towards mercury than strain Pseudomonas sp. ORNaP2. These differences between the Gram-negative Pseudomonas and the Gram-positive Paenibacillus strain can be explained by different general adaptive response systems present in the two bacteria
Neighbourliness, conviviality, and the sacred in Athens’ refugee squats
To better understand the range of possibilities and opportunities for (co)existence available to displacement‐affected people, attention must be given to the thick webs of sociality shaping interactions in situations of mass displacement. This paper makes the case that refugee squats in Athens are distinct spaces wherein different understandings of (co)existence converge – spaces whose production is contingent on support from neighbourly relations and networks that are mediated in moments through conceptions of conviviality informed by religion. Based on ethnographic work carried out in 2016 and a spatial analysis of refugee squats in Athens, this paper emphasises neighbourliness and conviviality as they relate to sacred understandings of coexistence. This helps highlight the limits built in to thinking about the movement of refugees from the global South through Euro‐centric ontologies of the social. More than this, following postcolonial debates on the decentring of knowledge production, the research makes manifest how Islamic socio‐cultural memories of jiwār or a right of neighbourliness complicate geographies of humanitarianism that make stark binary assumptions between religious and secular space. In turn, the evidence from Athens indicates that refugee perspectives on neighbourliness are imperfectly translated by migrant rights activists as solidarity, obscuring the different ways Muslim structures of feeling contribute to the production of refugee squats
A new icriodontid conodont cluster with specific mesowear supports an alternative apparatus motion model for Icriodontidae
Increasing numbers of conodont discoveries with soft tissue preservation, natural assemblages and fused clusters of the hard tissue have strengthened the hypothesis regarding the function and mechanism of the conodont feeding apparatus. Exceptional fossil preservation serves as a solid basis for modern reconstructions of the conodont apparatus illustrating the complex interplay of the single apparatus elements. Reliable published models concern the ozarkodinid apparatus of Pennsylvanian and Early Triassic conodonts. Recognition of microwear and mammal-like occlusion, especially of platform elements belonging to individuals of the genus Idiognathodus, allows rotational closure to be interpreted as the crushing mechanism of ozarkodinid platform (P1) elements. Here we describe a new icriodontid conodont cluster of Caudicriodus woschmidti that consists of one pair of icriodontan (I) and 10 pairs of coniform (C1\ue2\u80\u935) elements, with I elements being preserved in interlocking position. The special kind of element arrangement within the fused cluster provides new insights into icriodontid apparatus reconstruction and notation of elements. However, orientation of coniform elements is limited to a certain degree by possible preservational bias. Four possible apparatus models are introduced and discussed. Recognition of specific wear on denticle tips of one of the icriodontan elements forms the basis for an alternative hypothesis of apparatus motion. Analysis of tip wear suggests a horizontal, slightly elliptical motion of opposed, antagonistically operating I elements. This is supported by similar tip wear from much better preserved, but isolated, elements of Middle Devonian icriodontids. More detailed interpretation of the masticatory movement will allow enhanced understanding of anatomical specifications, diet and palaeobiology of different euconodont groups
Spin-alignment and g-factor measurement of the = 12+ isomer in 192Pb produced in the relativistic-energy fragmentation of a 238U beam
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