Lensless polarimetric coded ptychography for high-resolution,high-throughput gigapixel birefringence imaging on a chip

Polarimetric imaging provides valuable insights into the polarization state of light interacting with a sample.It can infer crucial birefringence properties of specimens without using labels,thereby facilitating the diagnosis of diseases such as cancer and osteoarthritis.In this study,we present a novel polarimetric coded ptychography(pol-CP)approach that enables high-resolution,high-throughput gigapixel birefringence imaging on a chip.Our platform deviates from traditional lens-based systems by employing an integrated polarimetric coded sensor for lensless coherent diffraction imaging.Utilizing Jones calculus,we quantitatively determine the birefringence retardance and orientation information of biospecimens from the recovered images.Our portable pol-CP prototype can resolve the 435 nm linewidth on the resolution target,and the imaging field of view for a single acquisition is limited only by the detector size of 41 mm2.The prototype allows for the acquisition of gigapixel birefringence images with a 180 mm^(2) field of view in~3.5 min,a performance that rivals high-end whole slide scanner but at a small fraction of the cost.To demonstrate its biomedical applications,we perform high-throughput imaging of malaria-infected blood smears,locating parasites using birefringence contrast.We also generate birefringence maps of label-free thyroid smears to identify thyroid follicles.Notably,the recovered birefringence maps emphasize the same regions as autofluorescence images,underscoring the potential for rapid on-site evaluation of label-free biopsies.Our approach provides a turnkey and portable solution for lensless polarimetric analysis on a chip,with promising applications in disease diagnosis,crystal screening,and label-free chemical imaging,particularly in resource-constrained environments.

Guide to forensic pathology practice for death cases related to coronavirus disease 2019(COVID-19)(Trial draft)

Autopsy is of great significance for elucidating the pathological changes,pathogenesis and cause of death of Coronavirus Disease 2019(COVID-19)and can provide a theoretical basis for scientific and accurate prevention and control of its outbreak.Based on related laws and regulations,such as the Law of the People's Republic of China on Prevention and Control of Infectious Diseases,clinical manifestations and epidemiological characteristics of COVID-19 and guidelines on the prevention and control of this epidemic,combined with the practical work of forensic pathology examinations,we developed the Guide to Forensic Pathology Practice for Death Cases Related to Coronavirus Disease 2019(COVID-19)(Trial Draft).This guide describes the background investigation of the death cases,autopsy room requirements,personal pre-vention and protections,external examinations,autopsy practices and auxiliary examinations,and thus offers a reference for forensic and pathological examination institutions and staff.

Sudden Cardiac Death and Cardiac Sodium Channel Diseases

Sudden cardiac death(SCD),accounting for a substantial part of the forensic autopsy,is a leading cause of mortality worldwide.Lethal arrhythmia due to sodium channel diseases is recognized as one of the most prevalent etiologies of SCD.In these disorders,defective cardiomyocytes,including the pacemaker and the working cardiomyocytes,would manifest as abnormal electrical activity and morphology,thereby predisposing individuals to SCD.It is always a problem for forensic pathologists to adjudicate a sudden death caused by sodium channel diseases since structural changes in those cases are often inconspicuous.With the advent of the molecular autopsy,forensic pathologists can conduct targeted gene testing to identify the risk of SCD for family members of the probands.This review aims to discuss the relationship between SCD and sodium channel diseases,clarify the underlying mechanisms,and provide prophylactic suggestions for the relatives of SCD patients at risk.