What landscape elements are needed for hospital healing spaces? Evidence from an empirical study of 10 compact hospitals.

Background: Modern medical research shows that a rationally planned landscape environment helps patients recover. With the growing number of hospital patients and the tightening of per capita medical landscape land, the use of limited landscape resources to serve patients has become challenging. Methods: This study focused on the landscape environment of 10 hospitals in Guangdong Province, China. Based on the KANO theoretical model, a survey questionnaire was designed and administered to 410 participants. The data were analyzed based on demand attributes, importance, sensitivity, and group differences. Results: The maintenance requirements were the most important item in the sensitivity ranking. Furthermore, the analysis revealed that the users need a safe, quiet, and private environment, owing to their higher requirements, including visual healing, rehabilitation activities, shading and heat preservation, and medical escort. Moreover, adolescents and older adult patients have common and contradictory environmental needs. For example, the landscape environment should provide both an active space and a quiet rehabilitation environment. Conclusion: This study evaluates how landscape resources can be better utilized from the perspective of the user and expands the theory of healing landscapes, which has practical implications for hospital renovation and landscape environment strategies.

Remote transport of high-dimensional orbital angular momentum states and ghost images via spatial-mode-engineered frequency conversion.

The efficient transport and engineering of photonic orbital angular momentum (OAM) lie at the heart of various related classical and quantum applications. Here, by leveraging the spatial-mode-engineered frequency conversion, we realize the remote transport of high-dimensional orbital angular momentum (OAM) states between two distant parties without direct transmission of information carriers. We exploit perfect vortices for preparing high-dimensional yet maximal O AM entanglement. Based on nonlinear sum-frequency generation working with a strong coherent wave packet and a single photon, we conduct the Bell-like state measurements for high-dimensional perfect vortices. We experimentally achieve an average transport fidelity 0.879 ± 0.048 and 0.796 ± 0.066 for a complete set of 3-dimensional and 5-dimensional OAM mutually unbiased bases, respectively. Furthermore, by exploring the full transverse entanglement, we construct another strategy of quantum imaging with interaction-free light. It is expected that, with the future advances in nonlinear frequency conversion, our scheme will pave the way for realizing truly secure high-dimensional quantum teleportation in the upcoming quantum network.

Turbulence-resilient detection of the rotational Doppler effect with cylindrical vector beams.

Recent years have witnessed a growing research interest in the rotational Doppler effect associated with orbital angular momentum of light, emerging as a powerful tool to detect rotating bodies in remote sensing. However, this method, when exposed to the turbulence in a realistic environment, has some severe limitations, leading to the unrecognizable rotational Doppler signals overwhelmed in background noise. Here we put forward a concise yet efficient method that enables the turbulence-resilient detection of the rotational Doppler effect with cylindrical vector beams. Specifically, by adopting the polarization-encoded dual-channel detection system, the low-frequency noises caused by turbulence can be individually extracted and subtracted, and thus mitigate the effect of turbulence. We demonstrate our scheme by conducting proof-of-principle experiments, whose results manifest the feasibility of a practical sensor to detect the rotating bodies in non-laboratory conditions.

Non-orthogonal polarization encoding/decoding assisted by structured optical pattern recognition.

The complex vector beams yield up an abundance of polarization information that has not yet been well utilized in information encoding. In this paper, we propose a polarization encoding scheme with the non-orthogonal polarization states using a stationary vector beam. Recognizing those non-orthogonal polarization states is assisted by the structured patterns of the single vector beams under different polarization projections. We show that one can achieve different capacities of encoding bits by changing the step of the polarization angle with the single vector beam. We also demonstrate the non-orthogonal polarization encoding scheme can be well decoded with the machine learning classification algorithm. A 64×64 gray image is successfully transmitted by using 4 bits/symbol encoding-decoding scheme with 99.94 % transmission accuracy. Besides, by extending the encoding-decoding scheme to 8 bits/symbol based on the same single vector beam, we achieve a higher transmission rate with 65.58% transmission accuracy. Our work holds promise for small-angle non-orthogonal polarization encoding for free-space optical communications.