Maximum Planar Subgraph on Graphs not Contractive to K5 or K3,3

The maximum planar subgraph problem is well studied. Recently, it has been shown that the maximum planar subgraph problem is NP-complete for cubic graphs. In this paper we prove shortly that the maximum planar subgraph problem remains NP-complete even for graphs without a minor isomorphic to K5 or K3,3 , respectively

Safety and efficacy of a lifestyle intervention for pregnant women to prevent excessive maternal weight gain: a cluster-randomized controlled trial

Background: Excessive gestational weight gain (GWG) is associated with short- and long-term health problems among mothers and their offspring. There is a strong need for effective intervention strategies targeting excessive GWG to prevent adverse outcomes. Methods: We performed a cluster-randomized controlled intervention trial in eight gynecological practices evaluating the feasibility and effectiveness of a lifestyle intervention presented to all pregnant women; 250 healthy, pregnant women were recruited for the study. The intervention program consisted of two individually delivered counseling sessions focusing on diet, physical activity, and weight monitoring. The primary outcome was the proportion of pregnant women exceeding weight gain recommendations of the Institute of Medicine (IOM). Secondary outcome variables were maternal weight retention and short-term obstetric and neonatal outcomes. Results: The intervention resulted in a lower proportion of women exceeding IOM guidelines among women in the intervention group (38\%) compared with the control group (60\%) (odds ratio (OR): 0.5; 95\% confidence interval (CI): 0.3 to 0.9) without prompting an increase in the proportion of pregnancies with suboptimal weight gain (19\% vs. 21\%). Participants in the intervention group gained significantly less weight than those in the control group. Only 17\% of the women in the intervention group showed substantial weight retention of more than 5 kg compared with 31\% of those in the control group at month four postpartum (pp) (OR: 0.5; 95\% CI: 0.2 to 0.9). There were no significant differences in obstetric and neonatal outcomes. Conclusions: Lifestyle counseling given to pregnant women reduced the proportion of pregnancies with excessive GWG without increasing suboptimal weight gain, and may exert favorable effects on pp weight retention

The partial inverse minimum cut problem with

The partial inverse minimum cut problem is to minimally modify the capacities of a digraph such that there exists a minimum cut with respect to the new capacities that contains all arcs of a prespecified set. Orlin showed that the problem is strongly NP-hard if the amount of modification is measured by the weighted L1-norm. We prove that the problem remains hard for the unweighted case and show that the NP-hardness proof of Yang [RAIRO-Oper. Res. 35 (2001) 117–126] for this problem with additional bound constraints is not correct