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A cat-state is a superposition of two coherent states with amplitudes $\alpha_{0}$ and $-\alpha_{0}$. Recent experiments create cat states in a microwave cavity field using superconducting circuits. As with degenerate parametric oscillation (DPO) in an adiabatic and highly nonlinear limit, the states are formed in a signal cavity mode via a two-photon dissipative process induced by the down conversion of a pump field to generate pairs of signal photons. The damping of the signal and the presence of thermal fluctuations rapidly decoheres the state, and the effect on the dynamics is to either destroy the possibility of a cat state, or else to sharply reduce the lifetime and size of the cat-states that can be formed. In this paper, we study the effect on both the DPO and microwave systems of a squeezed reservoir coupled to the cavity. While the threshold nonlinearity is not altered, we show that the use of squeezed states significantly lengthens the lifetime of the cat states. This improves the feasibility of generating cat states of large amplitude and with a greater degree of quantum macroscopic coherence, which is necessary for many quantum technology applications. Using current experimental parameters for the microwave set-up, which requires a modified Hamiltonian, we further demonstrate how squeezed states enhance the quality of the cat states that could be formed in this regime. Squeezing also combats the significant decoherence due to thermal noise, which is relevant for microwave fields at finite temperature. By modeling a thermal squeezed reservoir, we show that the thermal decoherence of the dynamical cat states can be inhibited by a careful control of the squeezing of the reservoir. To signify the quality of the cat state, we consider different signatures including fringes and negativity, and the $C_{l_{1}}$ measure of quantum coherence.

Background Following enhanced malaria control measures, such as nationwide free distribution of insecticide-treated bed nets (ITN) by the government of Cameroon, its impact on malariometric and red cell indices in children ≤14 years in Muea, in the Mount Cameroon area was evaluated. Methods Two cross-sectional studies were conducted during the malaria transmission season (March-July) in 2006 (baseline) and 2013 (follow-up), respectively. The investigative methods included the use of a questionnaire to assess ITN use and coverage, clinical evaluation and laboratory investigations. Blood sample collected from each child was used for the preparation of blood films for detection of malaria parasites and density as well as full blood count determination using standard procedures and also an automated haematology analyzer. Results The majority of children (81.5%) possessed an ITN in 2013. The proportion of effective users of ITN increased significantly from 20.9% (CI = 17.3-25%) in 2006 to 35.2% (CI = 31–39.7%) in 2013. The highest relative risk reduction in prevalence during the follow-up study was observed in malaria anaemia (79%, CI = 58.0-69.1% [69.1 to 14.5%]), followed by gametocytaemia (71.6%, CI = 58.9-80.3% [25.6 to 7.3%]), anaemia (64%, CI = 58.0-69.1% [80.1 to 28.9%]), and malaria parasitaemia (57.2%, CI = 51.4-62.3% [85.4 to 36.6%]). In the baseline survey, the prevalence of splenomegaly was significantly highest (χ2 = 18.3, P