In Situ Constructing Ultrafast Ion Channel for Promoting High-Rate Cycle Stability of Nano-Na3V2(PO4)3 Cathode.

Encapsulating nanomaterials in carbon is one of the main ways to increase the cathode stability, but it is difficult to simultaneously optimize the rate capacity and enhance durability derived from the insufficient ion transport channels and deficient ion adsorption sites that constipate the ion transport and pseudocapacitive reaction. Herein, we develop the ligand-confined growth strategy to encapsulate the nano-Na3V2(PO4)3 cathode material in various carbon channels (microporous, mesoporous, and macroporous) to discriminate the optimal carbon channels for synchronously improving rate capacity and holding the high-rate cycle stability. Benefiting from the unobstructed ion/charge transport channels and flexible maskant created by the interconnected mesoporous carbon channels, the prepared Na3V2(PO4)3 nanoparticles confined in mesoporous carbon channel (Mes-NVP/C) achieve a discharge-specific capacity of 70 mAh g-1 even at the ultrahigh rate of 100 C, higher than those of the Na3V2(PO4)3 nanoparticles confined in microporous and macroporous carbon channel (Micr-NVP/C and Macr-NVP/C), respectively. Significantly, the capacity retention rate of Mes-NVP/C after 5000 cycles at 20 C is as high as 90.48%, exceeding most of the reported work. These findings hold great promise for traditional cathode materials to synergistically realize fast charging ability and long cycle life.

Spin-orbit Rabi oscillations in optically synthesized magnetic fields.

Rabi oscillation has been proven to be one of the cornerstones of quantum mechanics, triggering substantial investigations in different disciplines and various important applications both in the classical and quantum regimes. So far, two independent classes of wave states in the Rabi oscillations have been revealed as spin waves and orbital waves, while a Rabi wave state simultaneously merging the spin and orbital angular momentum has remained elusive. Here we report on the experimental and theoretical observation and control of spin-orbit-coupled Rabi oscillations in the higher-order regime of light. We constitute a pseudo spin-1/2 formalism and optically synthesize a magnetization vector through light-crystal interaction. We observe simultaneous oscillations of these ingredients in weak and strong coupling regimes, which are effectively controlled by a beam-dependent synthetic magnetic field. We introduce an electrically tunable platform, allowing fine control of transition between different oscillatory modes, resulting in an emission of orbital-angular-momentum beams with tunable topological structures. Our results constitute a general framework to explore spin-orbit couplings in the higher-order regime, offering routes to manipulating the spin and orbital angular momentum in three and four dimensions. The close analogy with the Pauli equation in quantum mechanics, nonlinear optics, etc., implies that the demonstrated concept can be readily generalized to different disciplines.

Emergency surgery of intra-articular calcaneal fractures using sinus tarsi approach with modified reduction technique.

BACKGROUND: The purpose of this study was to evaluate emergency surgery of calcaneal fractures using the sinus tarsi approach (STA) with modified reduction technique in terms of complication rates, iconography results and functional outcome. METHODS: We evaluated the outcomes of 26 patients treated in an emergency using STA with modified reduction technique. For that, we assessed Böhler´s angle, Gissane angle, reduction of the calcaneal body, and posterior facet, the visual analog scale (VAS), American Orthopaedic Foot and Ankle Society (AOFAS) score, complications, preoperative time, operative time, and in-hospital time. RESULTS: Recovery of calcaneal anatomy and articular surface were found at final follow-up. The mean Böhler´s angle at final follow-up were 30.68° ± 3.69°, of which was 15.02° ± 3.88° preoperatively (p < 0.001). The mean Gissane angle at final follow-up were 114.54° ± 11.16° of which was 88.86° ±10.96° preoperatively (p < 0.001). All cases had the varus/valgus angle of the tuber within 5 degrees. At the final follow-up, the mean AOFAS score was 89.23 ± 4.63, and the VAS score was 22.73 ± 6.5. CONCLUSIONS: Emergency surgery using STA with modified reduction technique is reliable, effective, and safe for treatment of calcaneal fractures. This technique can bring good clinical outcomes and a low rate of wound complications, reducing the in-hospital time, costs, and accelerating rehabilitation.

Theoretical study of freely propagating high-spatial-frequency optical waves.

When it comes to the high-spatial-frequency electromagnetic waves, we usually think of them as the evanescent waves which are bounded at the near-field surface and decay along with propagation distance. A conventional wisdom tells us that the high-spatial-frequency waves cannot exist in the far field. In this work, we show, however, that these high-spatial-frequency waves having wavenumbers larger than the incident one can propagate freely to the far-field regions. We demonstrate theoretically a technique, based on an abrupt truncation of the incident plane wave, to generate these intriguing waves. The truncation functions describing the slit and the complementary slit are considered as typical examples. Our results show that both the slit structures are able to produce the high-spatial-frequency wave phenomena in the far field, manifested by their interference fringes of the diffracted waves. This work introduces the high-spatial-frequency propagating waves. Therefore, it may trigger potential investigations on such an interesting subject, e.g., one may design delicate experiment to confirm this prediction. Besides, it would stimulate potential applications such as in superresolution and precise measurement.

Diffraction-limit focusing using a 60-nm-thick spiral slit.

We demonstrate a technique for diffraction-limit focusing, on the basis of a spatial truncation of incident light using spirally structured slit motifs. The spiral pattern leads to a global phase domain where the diffractive wave vectors are distributed in phase. We fabricate such a spiral pattern on a 60-nm-thick metallic film, capable of converting an orbital-angular-momentum beam to a non-helical high-resolution diffractive focusing beam, resulting in a high numerical aperture of 0.89 in air, and of up to 1.07 in an oil-immersion scenario. The topological complementarity between the incident beam and the slit motifs generates broadband subwavelength focusing. The idea can be extended to large-scale scenarios with larger constituents. The presented technique is more accessible to low-cost fabrications as compared with metasurface-based focusing elements.

Localization-to-delocalization transition of light in frequency-tuned photonic moiré lattices.

We demonstrate in a numerical manner the intriguing localization-to-delocalization transition of light in frequency-tuned photonic moiré lattices, both in the zero-order and the higher-order regimes of light waves. We present a different technique to realize the composite photonic lattices, by means of two relatively twisted sublattices with different modulated lattice constants. Even though various kinds of photonic patterns including the commensurable and the incommensurable lattices can be well constructed, the observed transition between the localization and the delocalization of light field is moiré angle-independent. This angle-insensitive property was not reported before, and cannot be achieved by those photonic moiré lattices that are all moiré angle-dependent. We reveal that the obtained phase transition of light is robust to the changes of refractive index modulation of the photonic lattices. Moreover, we reveal that the effect of moiré angle-independent transition of light can be extended to the higher-order vortex light field, hence allowing prediction, for the first time to our knowledge, of both the localization and the delocalization of the vortex light field in the photonic lattices.

Vector vortex state preservation in Fresnel cylindrical diffraction.

The vector vortex light beam, which exhibits a space-variant polarization state and is coupled with orbital angular momentum of light, has been drawing much attention due to its fundamental interest and potential applications in a wide range. Here we reveal both theoretically and experimentally that a diffractive structure having cylindrical symmetry is shown to be transparent for the vector vortex state of light with arbitrary topology. We demonstrate such an intriguing phenomenon in the Fresnel diffraction condition, where the vector Helmholtz wave equation can be utilized in the paraxial regime. Our demonstration has implications in control and manipulation of vector vortex light beams in diffractive optics, and hence, it may find potential applications.

Applications of PET in Diagnosis and Prognosis of Leukemia.

As a malignant hematopoietic stem cell disease, leukemia remains life-threatening due to its increasing incidence rate and mortality rate. Therefore, its early diagnosis and treatment play a very important role. In the present work, we systematically reviewed the current applications and future directions of positron emission tomography (PET) in patients with leukemia, especially 18F-FDG PET/CT. As a useful imaging approach, PET significantly contributes to the diagnosis and treatment of different types of leukemia, especially in the evaluation of extramedullary infiltration, monitoring of leukemia relapse, detection of Richter's transformation (RT), and assessment of the inflammatory activity associated with acute graft versus host disease. Future investigations should be focused on the potential of PET/CT in the prediction of clinical outcomes in patients with leukemia and the utility of novel radiotracers.

Aperiodic Vogel spirals for broadband optical wave focusing.

We demonstrate both experimentally and numerically a new type of hole array structure that exhibits optically diffractive focusing phenomenon. The hole arrays are designed based on the aperiodic Vogel spirals. In contrast to periodic and quasi-periodic hole arrays that contain discrete Bragg peaks in reciprocal space, the Vogel spiral hole arrays have particularly continuous Fourier components with circular symmetry, which enables optical wave focusing into a diffraction-limited hotspot for a wide range of incident wavelengths. We further demonstrate that the diffracted fields contain local orbital angular momentum (OAM) leading to rotations of the diffractive circular rings around the center, although the total OAM is zero.

[Hardware Implementation of Numerical Simulation Function of Hodgkin-Huxley Model Neurons Action Potential Based on Field Programmable Gate Array].

Neuron is the basic unit of the biological neural system. The Hodgkin-Huxley (HH) model is one of the most realistic neuron models on the electrophysiological characteristic description of neuron. Hardware implementation of neuron could provide new research ideas to clinical treatment of spinal cord injury, bionics and artificial intelligence. Based on the HH model neuron and the DSP Builder technology, in the present study, a single HH model neuron hardware implementation was completed in Field Programmable Gate Array (FPGA). The neuron implemented in FPGA was stimulated by different types of current, the action potential response characteristics were analyzed, and the correlation coefficient between numerical simulation result and hardware implementation result were calculated. The results showed that neuronal action potential response of FPGA was highly consistent with numerical simulation result. This work lays the foundation for hardware implementation of neural network.