Let A be an m × n integral matrix of rank n. We say that A has bounded minors if the maximum of the absolute values of the n × n minors is at most k, where k is a some natural constant. We will call that matrices like k-modular. We investigate an integer program max{cx : Ax ≤ b, x ∈ Zn} where A is k-modular. We say that A is almost unimodular (see [2, 5]) if it is 2-modular and the absolute val...

Research with minors, especially for preventive purposes, e.g., suicide prevention, investigating risk or self-destructive behaviors such as deviance, drug abuse, or suicidal behavior, is ethically sensitive. We present a Delphi study exploring the ethical implications of the needs formulated by researchers in an international pre-conference who would benefit from ethics support and guidance in...

A key stated objective of the Australian Plain Packaging Act 2011 is to influence smoking prevalence, in particular of minors. We use the Roy Morgan Single Source (Australia) data set on minors, (that is, Australians aged 14 to 17 years) over the time period January 2001 to December 2013 to analyze whether there is evidence that this goal has been achieved. We carry out a statistical trend anal...

It is well-known (Feige and Kilian [24], H̊astad [39]) that approximating the chromatic number within a factor of n1−ε cannot be done in polynomial time for ε > 0, unless coRP = NP. Computing the list-chromatic number is much harder than determining the chromatic number. It is known that the problem of deciding if the list-chromatic number is k, where k ≥ 3, is Πp2-complete [37]. In this paper, ...

The Depth First Search (DFS) algorithm is one of the basic techniques which is used in a very large variety of graph algorithms. Most applications of the DFS involve the construction of a depth-first spanning tree (DFS tree). In this paper, we give a complete characterization of all the graphs in which every spanning tree is a DFS tree. These graphs are called Total −DFS −Graphs. We prove that ...

A heavy traac limit theorem for networks of queues with multiple customer types. 27 We now compute the principal minors of D k 2 and D k 3. First consider D k 2. All the principal minors of order 2 are equal to 1. The principal minor corresponding to f1; 3; 4g is equal to 1 + 3 1 3 4 == 2 , and the remaining principal minors of order 3 are equal to 1. The determinant of the matrix itself is 1 ?...

Since 2007, the China Internet Network Information Center (CNNIC) has been investigating online behavior of Chinese youth. Until 1 December 2022, CNNIC released “Research Report on Usage Minors in 2021” which shows that penetration rate among minors is 96.8%, this means can no longer live without access to internet. With advancement technology and development internet age, smartphones are also ...

Motivated by the Eulerian ribbon graph minors, in this paper we introduce notion of checkerboard colourable minors for graphs and its dual: bipartite graphs. abstract graphs, another i.e. join are also introduced. Using these then give excluded minor characterizations classes plane

Vaccines currently recommended for adolescents by the Advisory Committee on Immunization Practices have the potential to improve the health of youth by preventing conditions such as: tetanus, pertussis, meningococcal disease, influenza, and genital warts, as well as later adult outcomes such as cervical and other human papillomavirus-related cancers. Adolescent vaccine coverage lags behind that...

BACKGROUND Because of specific methodological difficulties in conducting randomized trials, surgical research remains dependent predominantly on observational or non-randomized studies. Few validated instruments are available to determine the methodological quality of such studies either from the reader's perspective or for the purpose of meta-analysis. The aim of the present study was to devel...