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This study aims to assess the use of variational quantum imaginary time evolution for solving partial differential equations using real-amplitude ansätze with full circular entangling layers. A graphical mapping technique for encoding impulse functions is also proposed.

The Smoluchowski equation, including the Derjaguin–Landau–Verwey–Overbeek potential energy, is solved to simulate colloidal deposition on a planar wall. The performance of different types of entangling layers and over-parameterization is evaluated.

Colloidal transport can be modelled adequately with variational quantum simulations. Full circular entangling layers with real-amplitude ansätze lead to higher-fidelity solutions. In most cases, the proposed graphical mapping technique requires only a single bit-flip with a parametric gate. Over-parameterization is necessary to satisfy certain physical boundary conditions, and higher-order time-stepping reduces norm errors.

Variational quantum simulation can solve partial differential equations using near-term quantum devices. The proposed graphical mapping technique could potentially aid quantum simulations for certain applications.

This study shows a concrete application of variational quantum simulation methods in solving practically relevant partial differential equations. It also provides insight into the performance of different types of entangling layers and over-parameterization. The proposed graphical mapping technique could be valuable for quantum simulation implementations. The findings contribute to the growing body of research on using variational quantum simulations for solving partial differential equations.

State ownership has been common especially in industries with restricted competition. In Russia, state-controlled firms represent around 41 percent of the market value of all listed firms (Deloitte, 2015). Yet, there is a significant gap in the literature regarding the effects of various forms of government control in listed firms. The purpose of this paper is to fill this gap by exploring the impact of the complexity of state ownership and competition on the performance of Russian listed firms.

The sample consists of data for 72 firms (360 firm-years) in the Russian MOEX broad market index during 2011–2015. The complexity of state ownership is captured by studying forms of state control including majority/minority, direct/indirect, federal/regional, mixed structures and golden shares.

The authors find significant differences in performance relating to different forms of state ownership. State control is negatively related to firm valuation and the sales/employees ratio. Performance is weakest when state ownership takes the form minority, regional or direct ownership. State control through golden shares typically outperforms other state-controlled firms. The authors find indications of employment prioritization beyond the economical optimum. In addition, the relation between state ownership and profitability becomes positive in sectors where state firms appear to enjoy lower competition.

While the effects of state ownership have been studied on many markets, there is a lack of studies on the effects of different forms, or the complexity, of state ownership beyond direct and indirect ownership. The authors contribute to the literature on the performance effects of state ownership by studying a multitude of forms of governmental ownership as well as the role of competition in Russia. Especially the profitability of state-controlled firms is significantly affected by industry characteristics. Implications of the results are discussed both from firm and policy maker perspectives.

Awareness raising campaigns have been used to promote HIV prevention messages, including the expansion of HIV testing, but initiating such campaigns de novo can be costly. Both the Bronx, New York and Washington, DC have significant local HIV epidemics and a history of efforts to scale-up HIV testing. To build on prior HIV testing campaigns and create new messages based on consultation with diverse stakeholders, a partnership with a community-based clinical trial to enhance HIV testing and treatment was established. The purpose of this paper is to describe the history of HIV testing campaigns in the two jurisdictions, the awareness raising conducted in collaboration with the HIV Prevention Trials Network (HPTN) study (HPTN 065) and provide evidence of its effect in these two communities.

The foundation of prior campaigns allowed for expansion of social mobilization efforts to specific priority populations (gay men and other men who have sex with men), the most severely affected groups in both communities, and to expand the efforts to include clinical settings. New compelling and acceptable messages were shaped through engagement with community members and based on input from focus groups with target populations in each city.

By engaging the target population in the development of new messaging, HPTN 065 study successfully built on campaigns that were already underway in both jurisdictions and was able to use those messages and platforms to further normalize HIV testing.

Modifying and adapting existing messages saved time and resources, which can be important factors to consider in settings with limited resources or high media purchasing costs.

Efforts of this kind may ultimately help to decrease HIV transmission in large urban settings.