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The expanding realm of high‐frequency electronics necessitates materials with exceptional attributes: notably, a low dielectric constant (Dk) to minimize signal propagation delays, high thermal conductivity for effective heat dissipation, higher breakdown strength, and robust mechanical properties to withstand demanding operational environments. While cycloolefin copolymers (COC) excel in electrical insulation, chemical resistance, and mechanical durability, their intrinsic slightly higher dielectric constant compared to other polymers, along with challenges such as poor dispersibility and low compatibility with nanoparticles, hinder their full potential in this domain. Considering these drawbacks, this study fabricated a series of COC/mica composites by integrating natural mica particles into the COC matrix via a CTAB‐assisted surface modification of mica to enhance dispersibility and mitigating particle aggregation through in‐situ mixing and hot‐press methods. The resultant composites demonstrate an outstanding ultra‐low Dk of 1.44, marking a significant decrease of over 36% compared to pristine COC with a Dk of 2.26, along with exceptionally low dielectric loss (δ) of 0.00013 at the frequency of 10 GHz, high dielectric breakdown strength ~49.40 kV/mm and enhanced thermal conductivity up to 0.88 W/(m K) at 40% mica loading. Additionally, the composites heightened mechanical performances like tensile strength 69 MPa at 6.5% elongation at break, impact strength up to ~17.9 kJ × m−2, and exceptional water resistance with absorption below 0.097%. These exceptional ultra‐low dielectric performance with above mentioned properties can meet the stringent requirements of modern high‐frequency electronics packaging for next generation electronics development. Highlights: Surface modification by CTAB enhanced homogeneous dispersibility of composites.Achieved ultra‐low dielectric constant and loss compared to pure COC.Thermal conductivity improved significantly with incorporation of mica.Unlocking high‐frequency applications potential with ultralow Dk performance. [ABSTRACT FROM AUTHOR]

Introduction: Both doctors and nurses showed a greater risk of being exposed to different mental health conditions following mass casualties. This systematic review aims to synthesise the existing evidence on the prevalence of anxiety, depression and post-traumatic stress disorder and their associated risk factors among doctors and nurses following mass casualty incidents., Methods and Analysis: Seven electronic databases (PubMed, PsycINFO, MEDLINE Ovid, Embase, CINAHL, Web of Science and Nursing & Allied Health database) will be searched from 2010 to 2022 with peer-reviewed articles in English language using the predefined keywords. Two reviewers will independently screen the titles and abstracts, as well as review the full texts using the eligibility criteria, then extract data independently. The National Institutes of Health Quality Assessment Tools (NIH-QAT) for quantitative studies, the Critical Appraisal Skills Programme (CASP) Checklist for qualitative studies and the Mixed-Methods Appraisal Tool (MMAT) for mixed-method studies will be used to measure the quality appraisal of eligible studies. A third reviewer will resolve the discrepancies when the two reviewers cannot reach an agreement in any step. The result from the eligible studies will be described following narrative synthesis with the key characteristics and findings of the included studies, and meta-analysis will be performed, if applicable., Ethics and Dissemination: This systematic review deals with existing published studies without any personally identifiable information of participants. Therefore, ethical approval from the research committee is not required. Findings from this review will be disseminated in peer-reviewed journals and presented at relevant international conferences., Prospero Registration Number: CRD42023412852., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)