Consider a pair of group divisible designs (GDD) with block size 3, index λ = 1, and on the same points and groups. They are said to be orthogonal (OGDD) if (i) whenever two blocks, one from each design, intersect in two points, the third points are in different groups; and (ii) two disjoint pairs of points defining intersecting triples in one GDD fail to do so in the other. A question posed by...

Suppose Kv is the complete undirected graph with v vertices. Let K4 − e be the graph obtained from K4 by removing one edge. A (K4 − e) group divisible design (briefly (K4 − e)-GDD) of type h is a triple (X,G,B), where G is a partition of X into groups each of size h, B is an edge-disjoint decomposition of the edge set of Kh,h,...,h, the multipartite complete undirected graph with G as the parti...

Disease outbreaks of international public health importance continue to occur regularly; detecting and tracking significant new public health threats in countries that cannot or might not report such events to the global health community is a challenge. The Centers for Disease Control and Prevention's (CDC) Global Disease Detection (GDD) Operations Center, established in early 2007, monitors in...

Objective: To determine the thermal sum requirements in degrees days of development (GDD) varieties Avena sativa, Cuauhtémoc and Chihuahua by phenological stage its effect on accumulation total forage morphological component Güémez, Tamaulipas.
 Design/methodology/approach: The sowing was carried out plots 6×6 m four repetitions through mechanized preparation land, with doses 120 kg ha-1 s...

Growing degree days (GDD) is a tool to predict plant growth and can be adapted for use in any species, including cover crops. A limitation of the GDD calculation accurate temperature parameters used development. For most crop cardinal temperatures are not well defined literature, leading less GDD. The objective this study was determine eight Austrian winter pea (Pisum sativum), balansa clover (...

Irrigated agriculture is facing a serious problem of water scarcity, which could be mitigated by optimizing the application regulated deficit irrigation (RDI) strategies. For this reason, aim our study was to determine thresholds based on direct status indicators apricot trees under RDI maximize productivity. Three treatments were tested: (i) Control (CTL), irrigated at 100% crop evapotranspira...