background objective: to evaluate the utility of specific cut-off values for c- reactive protein (crp) and immature-to-total neutrophil ratio (i/t) as screening tests for meningitis in culture negative early onset sepsis (eos). materials and methods retrospective chart review of 97 newborns with culture negative sepsis who had lumbar puncture performed as part of the sepsis evaluation in a leve...

In the brain, spike trains are generated in time and presumably also interpreted as they unfold in time. Recent work (Oram et al., 1999; Baker and Lemon, 2000) suggests that in several areas of the monkey brain, individual spike times carry information because they reflect an underlying rate variation. Constructing a model based on this stochastic structure allows us to apply order statistics t...

In this article, a detailed study of the recently synthesized MAX phase borides M2SB (M = Zr, Hf and Nb) has been performed via first principles technique. Investigation mechanical hardness, elastic anisotropy, optical properties, dynamical stability thermal properties are considered for time. The estimated values stiffness constants moduli found in good agreement with available results. micro ...

The Poisson's ratio is a fundamental mechanical property that relates the resulting lateral strain to applied axial strain. Although this value can theoretically be negative, it is positive for nearly all materials, though negative values have been observed in so-called auxetic structures. However, nearly all auxetic materials are bulk materials whose microstructure has been specifically engine...

1186 Ó WILEY-VCH Verlag GmbH, D-69469 Weinheim, 1999 0935-9648/99/1410-1186 $ 17.50+.50/0 Adv. Mater. 1999, 11, No. 14 quenching to room temperature. As a result, the polarization bandwidth was found to increase by a factor of 2.4 over what was expected of a constant-pitch film. The increased bandwidth was attributed to a pitch gradient resulting from photoinduced racemization of the chiral dop...

Thermal convection in colloidal suspensions of nanosized particles is investigated. Representative examples for such materials are ferrofluids, but since we do not imply any external magnetic field, the description applies to nonmagnetic suspensions as well. With the grain size being large on molecular length scales, the particle mobility is extremely small, allowing to disregard the concentrat...

Chiral three-dimensional isotropic cubic lattices with rigid cubical nodules and multiple deformable ribs are developed and analyzed via finite element analysis. The lattices exhibit geometry dependent Poisson’s ratio that can be tuned to negative values. Poisson’s ratio decreases from positive to negative values as the number of cells increases. Isotropy is obtained by adjustment of aspect rat...

Auxetic behavior in low porosity metallic structures is demonstrated via a simple system of orthogonal elliptical voids. In this minimal 2D system, the Poisson's ratio can be effectively controlled by changing the aspect ratio of the voids. In this way, large negative values of Poisson's ratio can be achieved, indicating an effective strategy for designing auxetic structures with desired porosity.

The Poisson's ratio of a material characterizes its response to uniaxial strain. Materials normally possess a positive Poisson's ratio - they contract laterally when stretched, and expand laterally when compressed. A negative Poisson's ratio is theoretically permissible but has not, with few exceptions of man-made bulk structures, been experimentally observed in any natural materials. Here, we ...