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Poly(2,6‐dimethyl‐1,4‐phenylene oxide) (PPO) as a kind of low dielectric polymer has been applied in telecommunications. However, developing PPO based thermosetting resins with good comprehensive properties is highly challenging. Herein, an interpenetrating polymer network (IPN) design strategy for the preparation of methacrylate‐terminated oligo(2,6‐dimethyl‐1,4‐phenylene oxide) (SA9000) based thermosetting resins is presented. Two series of prepolymers are prepared by blending bisphenol A/furfurylamine benzoxazine (B‐f) or bisphenol A/aniline benzoxazine (B‐a) with SA9000. Then the IPN films are fabricated by the programmed temperature rising method with simultaneous polymerization reactions of both SA9000 and benzoxazines. Owing to the intermolecular interactions between SA9000 and benzoxazines, the polymerization peak temperatures of all prepolymers are lower than those of SA9000 and benzoxazines. In comparison with B‐a based films, B‐f/SA9000 films display better miscibility and higher thermal resistances over the entire composition range, due to the strengthened hydrogen bonding and higher cross‐linking density resulting from the presence of furan ring of B‐f. Specifically, B‐f/SA9000 films possess the advantages of low dielectric constants (2.296–2.475) and low‐loss grade dielectric losses (0.00550–0.00683) at 10 GHz. The current work provides a simple and effective path for the fabrication of high‐performance thermosetting PPO resins based on benzoxazine chemistry and IPN structure design. [ABSTRACT FROM AUTHOR]

Snce December 2016, the number of human infections vith avian influenza A(H7N9) virus in China has increased markedly (1,2), prompting concerns of pandemic influenza. Early signals of greater human-to-human transmissibility [...]

Since the first human infections with avian influenza A(H7N9) virus were identified in early 2013 (1), mainland China has experienced 5 epidemics of human infections with A(H7N9) virus (2). As [...]

Hepatitis B virus (HBV) causes [approximately equal to]240 million chronic infections and [approximately equal to]780,000 deaths from cirrhosis and liver cancer annually (1). Recognizing the large global disease burden, the [...]

The introduction of public health and social measures has been one of the key strategies to curb the transmission of the coronavirus disease 2019 (COVID-19). Such measures include nonpharmaceutical actions [...]

Problem In 2003, China's handling of the early stages of the epidemic of severe acute respiratory syndrome (SARS) was heavily criticized and generally considered to be suboptimal. Approach Following the SARS outbreak, China made huge investments to improve surveillance, emergency preparedness and response capacity and strengthen public health institutions. In 2013, the return on these investments was evaluated by investigating China's early response to the emergence of avian influenza A(H7N9) virus in humans. Local setting Clusters of human infection with a novel influenza virus were detected in China--by national surveillance of pneumonia of unknown etiology--on 26 February 2013. Relevant changes On 31 March 2013, China notified the World Health Organization (WHO) of the first recorded human infections with A(H7N9) virus. Poultry markets--which were rapidly identified as a major source of transmission of A(H7N9) to humans-- were closed down in the affected areas. Surveillance in humans and poultry was heightened and technical guidelines were quickly updated and disseminated. The health authorities collaborated with WHO in risk assessments and risk communication. New cases were reported promptly and publicly. Lessons learnt The relevant infrastructures, surveillance systems and response capacity need to be strengthened in preparation for future emergencies caused by emerging or existing disease threats. Results of risk assessments and other data should be released promptly and publicly and such release should not jeopardize future publication of the data in scientific journals. Coordination between public health and veterinary services would be stronger during an emergency if these services had already undertaken joint preparedness planning. Probleme En 2003, la gestion des premiers stades de l'epidemie du syndrome respiratoire aigu severe (SRAS) par la Chine a ete fortement critiquee et generalement consideree comme non optimale. Approche Apres l'epidemie de SRAS, la Chine a investi massivement pour ameliorer sa surveillance, sa preparation aux situations d'urgence et sa capacite de reponse, et pour renforcer les etablissements de sante publique. En 2013, le retour sur ces investissements a ete evalue par l'examen de la reponse precoce de la Chine a l'emergence du virus de la grippe aviaire A(H7N9) chez l'homme. Environnement local Des cas d'infection humaine au nouveau virus de la grippe ont ete detectes en Chine le 26 fevrier 2013 par le systeme de surveillance nationale des pneumonies d'etiologie inconnue. Changements significatifs Le 31 mars 2013, la Chine a notifie a l'Organisation mondiale de la Sante (OMS) les premieres infections humaines au virus A(H7N9) enregistrees. Les marches de volaille qui ont ete rapidement identifies comme des sources majeures de transmission du virus A(H7N9) a l'homme--ont ete fermes dans les zones touchees. La surveillance a ete renforcee chez l'homme et les volailles, et les recommandations techniques ont ete rapidement mises a jour et diffusees. Les autorites sanitaires ont collabore avec l'OMS dans les domaines de l'evaluation des risques et de la communication des risques. Les nouveaux cas ont ete signales rapidement et publiquement. Lecons tirees Les infrastructures concernees, les systemes de surveillance et la capacite de reponse doivent etre renforces en prevision des futures urgences causees par les menaces de maladies emergentes ou existantes. Les resultats des evaluations des risques et les autres donnees doivent etre communiques rapidement et publiquement, et ces communications ne doivent pas compromettre la publication ulterieure des donnees dans les revues scientifiques. La coordination entre les services de sante publique et les services veterinaires serait plus forte pendant une situation d'urgence si ces services avaient deja engage une planification prealable commune. Situacion En 2003, la gestion de China de las primeras etapas de la epidemia del sindrome respiratorio agudo severo (SRAS) se critico duramente y se considero Insuficiente por lo general. Enfoque Tras el brote de SRAS, China realizo grandes inversiones para mejorar la vigilancia, la preparacion para emergencias y la capacidad de respuesta, asi como para fortalecer las instituciones de salud publica. En 2013, se evaluo la rentabilidad de estas Inversiones mediante una investigacion sobre la respuesta temprana de China a la aparicion del virus de la gripe aviar A(H7N9) en humanos. Marco regional El 26 de febrero de 2013 se detectaron grupos de infecciones humanas con el nuevo virus de la gripe en China mediante la vigilancia nacional de la neumonia de etiologia desconocida. Cambios importantes El 31 de marzo de 2013, China comunico a la Organizacion Mundial de la Salud (OMS) las primeras infecciones humanas del virus A(H7N9) registradas. Los mercados de aves de corral, que se identificaron de inmediato como una fuente importante de transmision del virus A(H7N9) a los humanos, se cerraron en las zonas afectadas. Se reforzo la vigilancia en humanos y aves de corral a la vez que se actualizaron y difundieron las directrices tecnicas con rapidez. Las autoridades de salud colaboraron con la OMS en la evaluacion de los riesgos y la comunicacion de los riesgos. De inmediato, se anunciaron los nuevos casos publicamente. Lecciones aprendidas Deben reforzarse las infraestructuras pertinentes, los sistemas de vigilancia y la capacidad de respuesta como preparacion a las futuras emergencias causadas por la amenaza de enfermedades nuevas o existentes. Los resultados de las evaluaciones de riesgo y el resto de datos deben divulgarse rapida y publicamente, pero dicha divulgacion no debe poner en peligro la futura publicacion de los datos en las revistas cientificas. La coordinacion entre la salud publica y los servicios veterinarios seria mas fuerte durante una emergencia si estos servicios planificaran de antemano la preparacion conjunta., Problem Severe acute respiratory syndrome is a zoonotic viral infection that probably first occurred, in late 2002, in the south of Chinas Guangdong province. (1) Although the syndrome eventually spread [...]

Since 2004, the Chinese Center for Disease Control and Prevention (China CDC) has conducted surveillance for pneumonia of unknown etiology (PUE) to facilitate timely detection of novel respiratory pathogens, such [...]