Improved Multi-Person 2D Human Pose Estimation Using Attention Mechanisms and Hard Example Mining

In recent years, human pose estimation, as a subfield of computer vision and artificial intelligence, has achieved significant performance improvements due to its wide applications in human-computer interaction, virtual reality, and smart security. However, most existing methods are designed for single-person scenes and suffer from low accuracy and long inference time in multi-person scenes. To address this issue, increasing attention has been paid to developing methods for multi-person pose estimation, such as utilizing Partial Affinity Field (PAF)-based bottom-up methods to estimate 2D poses of multiple people. In this study, we propose a method that addresses the problems of low network accuracy and poor estimation of flexible joints. This method introduces the attention mechanism into the network and utilizes the joint point extraction method based on hard example mining. Integrating the attention mechanism into the network improves its overall performance. In contrast, the joint point extraction method improves the localization accuracy of the flexible joints of the network without increasing the complexity. Experimental results demonstrate that our proposed method significantly improves the accuracy of 2D human pose estimation. Our network achieved a notably elevated Average Precision (AP) score of 60.0 and outperformed competing methods on the standard benchmark COCO test dataset, signifying its exceptional performance

Asymmetric Reprogramming Capacity of Parental Pronuclei in Mouse Zygotes

It has been demonstrated that reprogramming factors are sequestered in the pronuclei of zygotes after fertilization, because zygotes enucleated at the M phase instead of interphase of the first mitosis can support the development of cloned embryos. However, the contribution of the parental pronucleus derived from either the sperm or the oocyte in reprogramming remains elusive. Here, we demonstrate that the parental pronuclei have asymmetric reprogramming capacities and that the reprogramming factors reside predominantly in the male pronucleus. As a result, only female pronucleus-depleted (FPD) mouse zygotes can reprogram somatic cells to a pluripotent state and support the full-term development of cloned embryos; male pronucleus-depleted (MPD) zygotes fail to support somatic cell reprogramming. We further demonstrate that fusion of an additional male pronucleus into a zygote greatly enhances reprogramming efficiency. Our data provide a clue to further identify critical reprogramming factors in the male pronucleus

One-Pot Three-Component Strategy for Functionalized 2‑Aminoimidazoles via Ring Opening of α‑Nitro Epoxides

Functionalized 2-aminoimidazole derivatives have been synthesized via a three-component domino reaction of α-nitroepoxides and cyanamide with a series of amines under mild conditions without the need for any additives. This reaction represents a practical process for the facile conversion of α-nitroepoxides to 2-aminoimidazoles via ring opening of epoxides

A Chemical Tuned Strategy to Develop Novel Irreversible EGFR-TK Inhibitors with Improved Safety and Pharmacokinetic Profiles

Gatekeeper T790 M mutation in EGFR is the most prevalent factor underlying acquired resistance. Acrylamide-bearing quinazoline derivatives are powerful irreversible inhibitors for overcoming resistance. Nevertheless, concerns about the risk of nonspecific covalent modification have motivated the development of novel cysteine-targeting inhibitors. In this paper, we demonstrate that fluoro-substituted olefins can be tuned to alter Michael addition reactivity. Incorporation of these olefins into the quinazoline templates produced potent EGFR inhibitors with improved safety and pharmacokinetic properties. A lead compound <b>5a</b> was validated against EGFR^WT, EGFR^T790M as well as A431 and H1975 cancer cell lines. Additionally, compound <b>5a</b> displayed a weaker inhibition against the EGFR-independent cancer cell line SW620 when compared with afatinib. Oral administration of <b>5a</b> at a dose of 30 mg/kg induced tumor regression in a murine-EGFR^L858R/T790M driven H1975 xenograft model. Also, <b>5a</b> exhibited improved oral bioavailability and safety as well as favorable tissue distribution properties and enhanced brain uptake. These findings provide the basis of a promising strategy toward the treatment of NSCLC patients with drug resistance