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ing a first step to an optimised treatment based on biological factors.Dynamical quantum phase transitions (DQPTs) are characterized by nonanalytic behaviors of physical observables as functions of time. When a system is subject to time-periodic modulations, the nonanalytic signatures of its observables could recur periodically in time, leading to the phenomena of Floquet DQPTs. In this work, we systematically explore Floquet DQPTs in a class of periodically quenched one-dimensional system with chiral symmetry. By tuning the strength of quench, we find multiple Floquet DQPTs within a single driving period, with more DQPTs being observed when the system is initialized in Floquet states with larger topological invariants. Each Floquet DQPT is further accompanied by the quantized jump of a dynamical topological order parameter, whose values remain quantized in time if the underlying Floquet system is prepared in a gapped topological phase. The theory is demonstrated in a piecewise quenched lattice model, which possesses rich Floquet topological phases and is readily realizable in quantum simulators like the nitrogen-vacancy center in diamonds. EN450 cost Our discoveries thus open a new perspective for the Floquet engineering of DQPTs and the dynamical detection of topological phase transitions in Floquet systems.Preclinical positron emission tomography (PET) is a sensitive and quantitative molecule imaging modality widely used in characterizing the biological processes and diseases in small animals. The purpose of this study is to investigate the methods to optimize a PET detector for high-resolution preclinical imaging. The PET detector proposed in this study consists of a 28 × 28 array of LYSO crystals 0.5 × 0.5 × 6.25 mm3in size, a wedged lightguide, and a 6 × 6 array of SiPMs 3 × 3 mm2in size. The simulation results showed that the most uniform flood map was achieved when the thickness of the lightguide was 2.35 mm. The quality of the flood map was significantly improved by suppressing the electronics noises using the simple threshold method with a best threshold. The peak-to-valley ratio of flood map improved 25.4% when the algorithm of ICS rejection was applied. An energy resolution (12.96% ± 1.03%) was measured on the prototype scanner constructed with 12 proposed detectors. Lastly, a prototype preclinic PET imager was constructed with 12 optimized detectors. The point source experiment was performed and an excellent spatial resolution (axial 0.56 mm, tangential 0.46 mm, radial 0.42 mm) was achieved with the proposed high-performance PET detectors.Uneven terrain in natural environments challenges legged locomotion by inducing instability and causing limb collisions. During the swing phase, the limb releases from the ground and arcs forward to target a secure next foothold. In natural environments leg-obstacle collisions may occur during the swing phase which can result in instability, and may require contact sensing and trajectory re-planning if a collision occurs. However, collision detection and response often requires computationally- and temporally-expensive control strategies. Inspired by low stiffness limbs that can pass past obstacles in small insects and running birds, we investigated a passive method for overcoming swing-collisions. We implemented virtual compliance control in a robot leg that allowed us to systematically vary the limb stiffness and ultimately its response to collisions with obstacles in the environment. In addition to applying a standard positional control during swing motion, we developed two virtual compliance methods (1) an isotropic compliance for which perturbations in thexandydirections generated the same stiffness response, and (2) a vertical anisotropic compliance in which a decrease of the upwardyvertical limb stiffness enabled the leg to move upwards more freely. The virtual compliance methods slightly increased variability along the limb’s planned pathway, but the anisotropic compliance control improved the successful negotiation of step obstacles by over 70% compared to isotropic compliance and positional control methods. We confirmed these findings in simulation and using a self-propelling bipedal robot walking along a linear rail over bumpy terrain. While the importance of limb compliance for stance interactions have been known, our results highlight how limb compliance in the swing-phase can enhance walking performance in naturalistic environments.Cubic phase AgSbS2nanocrystals (NCs) were synthesized by the hot-injection method, and they were inserted between the Al andp-Si to fabricate Al/AgSbS2/p-Si photodiode by the thermal evaporation method. AgSbS2NCs were characterized by XRD, SEM and TEM instruments to confirm the crystal phase, surface morphology as well as crystalline size. The XRD pattern revealed that the cubic crystalline structure of the AgSbS2. The spherical shapes and well surface morphology were affirmed by SEM and TEM analysis. Al/AgSbS2/p-Si photodiode was characterized byI-Vmeasurements depending on the light power intensity and byC-Vmeasurement for various frequencies.I-Vcharacteristics revealed that the Al/AgSbS2/p-Si exhibited good photodiode behavior and a high rectifying ratio. Various diode and detector parameters were extracted fromI-Vmeasurements, and they were discussed in detail. TheC-Vcharacteristics highlighted that the Al/AgSbS2/p-Si photodiode showed voltage and frequency dependent profile at the accumulation region. The fabricated Al/AgSbS2/p-Si photodiode can be thought for optoelectronic applications.For graphene-based 2D materials, charge transfer at the interface between graphene and ferromagnetic metal leads to many intriguing phenomena. However, because of the unidirectional spin orientation in ferromagnetic transition metals, interface interaction plays a detrimental role in diminishing the magnetic parameters on 2D surfaces. To overcome this issue, we have synthesized ultrathin 2D weak antiferromagneticβ-NiOOH layers on a graphene surface. By exploiting the charge transfer effect and tuning the thickness of the thinβ-NiOOH layers, conversion of ferromagnetism along with giant coercivity and the thermo-remnant magnetic memory effect were observed. As antiferromagnets have two spin orientations, transfer of charge at the interface breaks the nullifying effect of zero magnetization in antiferromagnets and the combined system behaves like a 2D ferrimagnet. Whenever, the sandwich structure ofβ-NiOOH/graphene/β-NiOOH is formed, it also shows interlayer exchange coupling those results in huge exchange bias and anomalous temperature dependence of coercivity.