Combined non-pharmacological interventions for newborn pain relief in two degrees of pain procedures: A randomized clinical trial.

BACKGROUND: Non-pharmacological interventions are effective neonatal pain reduction strategies. We aimed to study the effects of non-nutritive sucking (NNS) and swaddling on infants' behavioural and physiological parameters during shallow or deep heel stick procedures. METHOD: In this prospective, multi-centred, randomized controlled clinical trial, we enrolled 671 newborns. The infants undergoing shallow or deep heel stick procedures were randomized into four groups: oral sucrose (routine care, group S), oral sucrose combined with NNS (group NS), oral sucrose combined with swaddling (group SS) and oral sucrose combined with NNS and swaddling (group NSS). The behavioural responses were evaluated by the Revised Neonatal Facial Coding System and the physiological signals were monitored by electrocardiogram monitors. RESULTS: A significant synergistic analgesic effect was observed between the NS and SS groups in both the shallow (F = 5.952, p = 0.015) and deep heel stick (F = 7.452, p = 0.007) procedure. NSS group exhibited the lowest pain score. For the deep heel stick procedure, the NS group had a significantly lower increase in heart rate (HR)% and decrease in SPO2 % than the S group (F = 17.540, p = 0.000, F = 10.472, p = 0.001), while this difference was not observed in the shallow heel stick procedure. No difference was found between the S and SS groups, in terms of different physiological parameters. CONCLUSION: Non-nutritive sucking and swaddling had synergistic effects on pain relief when used with oral sucrose. For the deep heel stick procedure, oral sucrose combined with NNS and swaddling provided the best pain relief effect. For the shallow heel stick procedure, addition of NNS and swaddling did not improve the effects.

Compact engineering of path-entangled sources from a monolithic quadratic nonlinear photonic crystal.

An integrated realization of photonic entangled states becomes an inevitable tendency toward integrated quantum optics. Here we report the compact engineering of steerable photonic path-entangled states from a monolithic quadratic nonlinear photonic crystal. The crystal acts as a coherent beam splitter to distribute photons into designed spatial modes, producing the heralded single-photon and appealing beamlike two-photon path entanglement. We characterize the path entanglement by implementing quantum spatial beating experiments. Such a multifunctional entangled source can be further extended to the high-dimensional fashion and multiphoton level, which paves a desirable way to engineering miniaturized quantum light sources.

On-chip steering of entangled photons in nonlinear photonic crystals.

One promising technique for working toward practical photonic quantum technologies is to implement multiple operations on a monolithic chip, thereby improving stability, scalability and miniaturization. The on-chip spatial control of entangled photons will certainly benefit numerous applications, including quantum imaging, quantum lithography, quantum metrology and quantum computation. However, external optical elements are usually required to spatially control the entangled photons. Here we present the first experimental demonstration of on-chip spatial control of entangled photons, based on a domain-engineered nonlinear photonic crystal. We manipulate the entangled photons using the inherent properties of the crystal during the parametric downconversion, demonstrating two-photon focusing and beam-splitting from a periodically poled lithium tantalate crystal with a parabolic phase profile. These experimental results indicate that versatile and precise spatial control of entangled photons is achievable. Because they may be operated independent of any bulk optical elements, domain-engineered nonlinear photonic crystals may prove to be a valuable ingredient in on-chip integrated quantum optics.

Simultaneous optical parametric oscillation and intracavity second-harmonic generation based on a hexagonally poled lithium tantalate.

Simultaneous optical parametric oscillation and intracavity second-harmonic generation based on a hexagonally poled lithium tantalate is reported. Both the optical parametric oscillation and the cascaded noncollinear second-order harmonic generation processes reach a high efficiency. A variety of possible self-doubling optical parametric oscillation processes indicate this hexagonally poled lithium tantalate has potential applications as a compact multi-wavelength light source.

Transforming spatial entanglement using a domain-engineering technique.

We study the spatial correlation of a two-photon entangled state produced in a multistripe periodically poled LiTaO3 crystal by spontaneous parametric down-conversion. The far-field diffraction-interference experiments reveal that the transverse modulation of domain patterns transforms the spatial mode function of the two-photon state. This result offers an approach to prepare a novel type of two-photon state with a unique spatial entanglement by using a domain-engineering technique.

Frequency self-doubling optical parametric amplification: noncollinear red-green-blue light-source generation based on a hexagonally poled lithium tantalate.

Simultaneous generation of noncollinear red, green, and blue light from a single hexagonally poled lithium tantalate is reported. It results from the frequency self-doubling optical parametric amplification process, a process of second-order harmonic generation cascaded optical parametric amplification in a single-pass setup. The temperature and spectrum detuning characters of each cascaded quasi-phase-matching process are studied. This unique red-green-blue light source has potential applications in laser display and other laser industries.