Whole-cell 3D STORM reveals interactions between cellular structures with nanometer-scale resolution.

The ability to directly visualize nanoscopic cellular structures and their spatial relationship in all three dimensions will greatly enhance our understanding of molecular processes in cells. Here we demonstrated multicolor three-dimensional (3D) stochastic optical reconstruction microscopy (STORM) as a tool to quantitatively probe cellular structures and their interactions. To facilitate STORM imaging, we generated photoswitchable probes in several distinct colors by covalently linking a photoswitchable cyanine reporter and an activator molecule to assist bioconjugation. We performed 3D localization in conjunction with focal plane scanning and correction for refractive index mismatch to obtain whole-cell images with a spatial resolution of 20-30 nm and 60-70 nm in the lateral and axial dimensions, respectively. Using this approach, we imaged the entire mitochondrial network in fixed monkey kidney BS-C-1 cells, and studied the spatial relationship between mitochondria and microtubules. The 3D STORM images resolved mitochondrial morphologies as well as mitochondria-microtubule contacts that were obscured in conventional fluorescence images

Breaking the Diffraction Barrier: Super-Resolution Imaging of Cells

Anyone who has used a light microscope has wished that its resolution could be a little better. Now, after centuries of gradual improvements, fluorescence microscopy has made a quantum leap in its resolving power due, in large part, to advancements over the past several years in a new area of research called super-resolution fluorescence microscopy. In this Primer, we explain the principles of various super-resolution approaches, such as STED, (S)SIM, and STORM/(F)PALM. Then, we describe recent applications of super-resolution microscopy in cells, which demonstrate how these approaches are beginning to provide new insights into cell biology, microbiology, and neurobiology

A new highly anti-interference regularization method for ill-posed problems

The solution of inverse problems has many applications in mathematical physics. Regularization methods can be applied to obtain the solution of ill-conditioned inverse problems by solving a family of neighboring well-posed problems. Thus, it is significant to investigate the regularization methods to increase the accuracy and efficiency of the solution of inverse problems. In this work, a new regularization filter and the related regularization method based on the singular system theory of compact operator are proposed to solve ill-posed problems. The Cauchy problem of Laplace equation of the first kind is a kind of well-known ill-posed problem. Numerical tests show that the proposed regularization method can solve the Cauchy problems more efficiently under a proper selection of regularization parameters. Numerical results also show that the proposed method is especially effective in solving ill-posed problems with big perturbations

Experimental Investigation on the Influence of the Oil Return Hole on the Performance of R-32 Wet Compression Cycle

R-32 has been being one of the hot candidate for refrigerant substitute because of its better thermodynamic performance. In this study, the influence of wet compression on R-32 system performance was researched by theoretical analysis and experimental test firstly. The result showed that, with the suction dryness decreasing, the discharge temperature，and the volumetric efficiency, and the system performance decreased simultaneously. And then, on the base of the wet compression experiment test, the influence of the oil return hole in the gas-liquid separator on system performance of R32 wet compression was compared. The experimental results showed that, in wet compression, the decreasing rate, that the cooling capacity and EER decreased with the discharge temperature decreasing, decreased with the size of the oil return hole increasing. The increase of the oil return hole size was benefit to improve the system performance in wet compression. But it increased the risk of over wet compression or liquid impact for compressor under frosting and defrosting condition

Entanglement-assisted multi-aperture pulse-compression radar for angle resolving detection

Entanglement has been known to boost target detection, despite it being destroyed by lossy-noisy propagation. Recently, [Phys. Rev. Lett. 128, 010501 (2022)] proposed a quantum pulse-compression radar to extend entanglement's benefit to target range estimation. In a radar application, many other aspects of the target are of interest, including angle, velocity and cross section. In this study, we propose a dual-receiver radar scheme that employs a high time-bandwidth product microwave pulse entangled with a pre-shared reference signal available at the receiver, to investigate the direction of a distant object and show that the direction-resolving capability is significantly improved by entanglement, compared to its classical counterpart under the same parameter settings. We identify the applicable scenario of this quantum radar to be short-range and high-frequency, which enables entanglement's benefit in a reasonable integration time.Comment: 18 pages, 9 figure

Review of Fiber Optic Displacement Sensors

Displacement Measurements Are of Significant Importance in a Variety of Critical Scientific and Engineering Fields, Such as Gravitational Wave Detection, Geophysical Research, and Manufacturing Industries. Due to the Inherent Advantages Such as Compactness, High Sensitivity, and Immunity to Electromagnetic Interference, in Recent Years, Fiber Optic Sensors Have Been Widely Used in an Expansive Range of Sensing Applications, Ranging from Infrastructural Health Monitoring to Chemical and Biological Sensing. of Particular Interest Here, Fiber Optic Displacement Sensors Have Gained Wide Interest and Have Evolved from Basic Intensity Modulation-Based Configurations to More Advanced Structures, Such as Fiber Bragg Grating (FBG)-Based and Interferometric Configurations. This Article Reviews Specifically the Advanced Fiber Optic Displacement Sensing Techniques that Have Been Developed in the Past Two Decades. Details Regarding the Working Principle, Sensor Design, and Performance Measures of FBG-Based, Interferometers-Based (Including the Fabry-Perot Interferometer, the Michelson Interferometer, and the Multimode Interferometer), Microwave Photonics-Based, and Surface Plasmon Resonance-Based Fiber Optic Displacement Sensors Are Given. Challenges and Perspectives on Future Research in the Development of Practical and High-Temperature Tolerant Displacement Sensors Are Also Discussed