We present new algorithms for construction of performance driven Rectilinear Steiner Trees under the Elmore delay model. Our algorithms represent a departure f r om previous approaches in that we derive an explicit area/delay tradeo curve. We achieve this goal by limiting the solution space to the set of topologies induced b y a p ermutation on the sinks of the net. This constraint allows ecient identication of optimal solutions while still providing a rich solution space. We also incorporate simultaneous wire sizing. Our technique consistently p r o duces topologies equalling the performance o f previous approaches with substantially less area overhead.

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This paper presents a discussion of methods to solve multiple way partitioning problems under three different objective functions. A multicommodity flow fzeatmertt is proposed for partitioning without a size wmstrain~and an iterative improvement algorithm is proposed for partitioning with a size comt.rstint. This algoriti incorporates a top-down clustering technique to deal with the local minima problems in common heuristics, a novel multi-pin net model to capture the contributory moves, and a Primal-Dual iteration to enhance the iterative improvement.Experiments show good results in all tested cases over the algorithm proposal in [12]. Also, the effect of different objective functions is manifested through numerical tabulation.

Rumor is an important form of social interaction, and its spreading has a significant impact on human lives. In this paper, a rumor propagation model with latent period and varying population is considered, which assumes an ignorant individual first goes through a latent period after infection before becoming a spreader or a stifler. Agents that read the rumor but have not decided to spread it, stay in the latent period. By means of the Lyapunov function and LaSalle's invariant set theorem, we proved the global asymptotical stable results of the rumor-free equilibrium and the rumor-endemic equilibrium by using the Poincarè-Bendixson property. Then an optimal control problem is formulated, from the perspective of a manager in emergency events, to maximize positive social effects with rumor spreading when the emergency resources are under constraints. Control signals, such as science education and official medial coverage attempt to convert lurkers and spreaders into stiflers. By employing Pontryagin's maximum principle, the optimal solution is acquired when the emergency response incurs nonlinear costs. Finally, we outline some strategies for managers that can contribute to rumor control in an emergency event.

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PurposeCOVID-19 (Coronavirus Disease 2019) was first reported in December 2019 and quickly swept across China and around the world. Levels of anxiety and depression were increased among pregnant women during this infectious pandemic. Thyroid function is altered during stressful experiences, and any abnormality during early pregnancy may significantly affect fetal development and pregnancy outcomes. This study aimed to determine whether the COVID-19 pandemic induces thyroid hormone changes in early pregnant women.MethodsThis study comprised two groups of pregnant women in Shanghai in their first trimester – those pregnant women before the COVID-19 outbreak from January 20, 2019, to March 31, 2019 (Group 1) and those pregnant during the COVID-19 outbreak from January 20, 2020, to March 31, 2020 (Group 2). All women were included if they had early pregnancy thyrotropin (TSH), free triiodothyronine (FT3), free thyroxine (FT4), total triiodothyronine (TT3), and total thyroxine (TT4) concentrations, thyroid peroxidase (TPO) antibody or thyroglobulin antibody (TgAb) available and did not have a history of thyroid diseases or received thyroid treatment before or during pregnancy. We used propensity score matching to form a cohort in which patients had similar baseline characteristics.ResultsAmong 3338 eligible pregnant women, 727 women in Group 1 and 727 in Group 2 had similar propensity scores and were included in the analyses. Pregnant women in Group 2 had significantly higher FT3 (5.7 vs. 5.2 pmol/L, P<0.001) and lower FT4 (12.8 vs. 13.2 pmol/L, P<0.001) concentrations compared with those in Group 1. Pregnant women in Group 2 were more likely to develop isolated hypothyroxinemia (11.6% vs. 6.9%, OR, 1.75 [95% CI, 1.20–2.53], P=0.003) than those in Group 1 but had a significantly lower risk of TgAb positivity (12.0% vs. 19.0%, OR, 0.58 [95% CI, 0.43–0.78], P<0.001).ConclusionPregnant women in their first trimester in Shanghai during the COVID-19 outbreak were at an increased risk of having higher FT3 concentrations, lower FT4 concentrations, and isolated hypothyroxinemia. The association between thyroid hormones, pregnancy outcomes, and the COVID-19 outbreak should be explored further.