In this paper we study the L(2, 1)-labeling problem on oriented planar graphs with particular attention on the subclasses of oriented prisms, Halin and cactus graphs. For these subclasses more accurate results are presented. keywords: L(2, 1)-labeling, oriented graph coloring, digraphs, prisms, Halin graphs, cacti.

Amphimela raydahensis sp. nov. is described from Garf Raydah Nature Reserve (Abha, Asir Province), southwestern Kingdom of Saudi Arabia. This species was collected using black light traps at different elevations dominated by cacti and wild olive trees. This is the first confirmed species of Amphimela known from the Arabian Peninsula.

BACKGROUND AND AIMS The genus Melocactus comprises 36 species of globose cacti with the most derived traits in the Cereeae tribe. It is the proper study system to examine what are the most derived reproductive strategies within that tribe. This study aims to characterize the reproductive biology and to estimate the mating system parameters of two Andean melocacti, Melocactus schatzlii and M. an...

The distance between two vertices u and v in a connected graph G is the number of edges lying shortest path (geodesic) them. A vertex x performs metric identification for pair (u, v) if only equality distances with implies that = (That is, different from x). minimum performing every defines dimension G. In this paper, we perform types polygonal cacti: chain cactus star cactus.

Noninvasive Healthcare Monitoring In article number 2102740, Kilwon Cho and co-workers report a sweat-collecting patch with directional sweat transportation, enabling fast continuous monitoring of by sensor. The wedge-shaped wettability patterns the are inspired spines cacti; channel shape, in combination superhydrophobic/superhydrophilic surface materials, induces unidirectional Laplace pressu...

Total embedding distributions have been known for only a few classes of graphs. In this paper the total embedding distributions of the cacti and the necklaces are obtained. Furthermore we obtain the total embedding distributions of all graphs with maximum genus 1 by using the method of this paper.