Spectral norm and energy of a digraph with respect to a VDB topological index.

The set of singular values of a digraph with respect to a vertex-degree based topological index is the set of all singular values of its general adjacency matrix. The spectral norm is the largest singular value and the energy the sum of the singular values. In this paper we characterize the digraphs which have exactly one singular value different from zero and the digraphs for which all singular values are equal.

Randić energy of digraphs.

We assume that is a directed graph with vertex set and arc set . A VDB topological index of is defined as where and denote the outdegree and indegree of vertices and , respectively, and is a bivariate symmetric function defined on nonnegative real numbers. Let be the general adjacency matrix defined as if , and 0 otherwise.

Sombor index of directed graphs.

Let be a digraph with set of arcs . The Sombor index of is defined as where and are the out-degree and in-degree of the vertices and of . When is a graph, we recover the Sombor index of graphs, a molecular descriptor recently introduced with a good predictive potential and a great research activity this year.

A global point prevalence survey of antimicrobial use in neonatal intensive care units: The no-more-antibiotics and resistance (NO-MAS-R) study.

Background: Global assessment of antimicrobial agents prescribed to infants in the neonatal intensive care unit (NICU) may inform antimicrobial stewardship efforts.

Methods: We conducted a one-day global point prevalence study of all antimicrobials provided to NICU infants. Demographic, clinical, and microbiologic data were obtained including NICU level, census, birth weight, gestational/chronologic age, diagnoses, antimicrobial therapy (reason for use; length of therapy), antimicrobial stewardship program (ASP), and 30-day in-hospital mortality.

[Intravenous thrombolysis for ischemic stroke: Experience in 54 patients].

Background: Intravenous thrombolysis with recombinant tissue plasminogen activator (rt-PA) reduces disability in patients with ischemic stroke. However, its implementation in Chilean public general hospitals has been slow and faces some difficulties.

Aim: To analyze the results of an intravenous thrombolysis protocol implementation in a public general hospital.

14-deoxyandrographolide as a platelet activating factor antagonist in bovine neutrophils.

14-Deoxyandrographolide (14-DAP) is a labdane diterpene isolated from Andrographis paniculata with previously reported calcium channel blocking activity. Its potential platelet activating factor (PAF) antagonistic activity in bovine neutrophils was assessed. 14-DAP, in concentrations between 10-100 microM, reduced the extracellular acidification rate and the intracellular alkalinization in a dose-dependent manner.