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101.
【目的】 分析国际顶级综合类科技期刊公众传播模式及特点,为我国科技期刊公众传播能力建设提供建议。【方法】 以Altmetric Top 100入选论文数量最多的Nature、Science和PNAS三刊为研究对象,剖析其在公众传播产品、媒体传播体系和新闻媒体人才支撑等方面的模式和特征。对照分析我国最有影响力的综合类科技期刊《国家科学评论》和《科学通报》的公众传播特点。【结果】 以《国家科学评论》和《科学通报》为代表的我国综合类科技期刊的公众传播能力提升迅速,但仍存在新闻传媒人才短缺、期刊集约化程度不高、公众传播机制尚未建立等问题。【结论】 我国综合类科技期刊需要着力增强传媒人才培育、集约化品牌发展、公众传播机制建设,以促进我国科技期刊公众传播能力提升。 相似文献
102.
Ladislav Pila Lucie Kvasni
kov Stanislavsk Roman Kvasni
ka Richard Hartman Ivana Tich 《Nutrients》2021,13(6)
Social media platforms have become part of many people’s lives. Users are spending more and more time on these platforms, creating an active and passive digital footprint through their interaction. This footprint has high research potential in many research areas because understanding people’s communication on social media is essential in understanding their values, attitudes, experiences and behaviors. Researchers found that the use of social networking sites impacts adolescents’ eating behavior. If we define adolescents as individuals between ages 10 and 24 (WHO’s definition), 76% of USA young people at age 18–24 use Instagram, so the Instagram social network analysis is important for understanding young people’s expressions in the context of healthy food. This study aims to identify the main topic associated with healthy food on the Instagram social network via hashtag and community analysis based on 2,045,653 messages created by 427,936 individual users. The results show that users most associate Healthy food with healthy lifestyle, fitness, weight loss and diet. In terms of food, these are foods that are Vegan, Homemade, Clean and Plant-based. Given that young people change their behavior in relation to people’s behavior on social networks, it is possible to use this data to predict their future association with healthy food characteristics. 相似文献
103.
Annika Molenaar Wei Yee Saw Linda Brennan Mike Reid Megan S. C. Lim Tracy A. McCaffrey 《Nutrients》2021,13(6)
Young adults are constantly exposed to energy-dense, nutrient-poor food and beverages, particularly through advertising. Exposure can influence poor food choices and negatively impact health. This study aimed to understand young adults’ attitudes and experiences associated with food-related advertisements, particularly on social media. This qualitative analysis involved n = 166 Australian 18 to 24-year-olds who were involved in a four-week online conversation on different areas relating to health, social media, and eating. Inductive thematic analysis was utilised on two forums on the recall and perceptions of food-related advertisements. Young adults commonly mentioned aspects of the marketing mix (promotion, product, price, and place) in food advertisements. Participants were more readily able to recall energy-dense, nutrient-poor food advertisements compared to healthy food-related advertisements. Digital advertisements were often discussed alongside the use of ad-blockers and algorithms which tailored their social media viewing to what they like. Participants felt constant exposure to unhealthy food advertisements hindered their ability to realise healthy eating behaviours and created feelings of guilt. This current analysis highlights the need to provide an advertising environment that appropriately motivates healthy eating and a food environment that allows healthy food to be the affordable and convenient option. 相似文献
104.
Andrew Kochan Shaun Ong Sabina Guler Kerri A Johannson Christopher J Ryerson Gillian C Goobie 《JMIR Public Health and Surveillance》2021,7(5)
BackgroundPatients use Facebook as a resource for medical information. We analyzed posts on idiopathic pulmonary fibrosis (IPF)-related Facebook groups and pages for the presence of guideline content, user engagement, and usefulness.ObjectiveThe objective of this study was to describe and analyze posts from Facebook groups and pages that primarily focus on IPF-related content.MethodsCross-sectional analysis was performed on a single date, identifying Facebook groups and pages resulting from separately searching “IPF” and “idiopathic pulmonary fibrosis.” For inclusion, groups and pages needed to meet either search term and be in English, publicly available, and relevant to IPF. Every 10th post was assessed for general characteristics, source, focus, and user engagement metrics. Posts were analyzed for presence of IPF guideline content, useful scientific information (eg, scientific publications), useful support information (eg, information about support groups), and potentially harmful information.ResultsEligibility criteria were met by 12 groups and 27 pages, leading to analysis of 523 posts. Of these, 42% contained guideline content, 24% provided useful support, 20% provided useful scientific information, and 5% contained potentially harmful information. The most common post source was nonmedical users (85%). Posts most frequently focused on IPF-related news (29%). Posts containing any guideline content had fewer likes or comments and a higher likelihood of containing potentially harmful content. Posts containing useful supportive information had more likes, shares, and comments.ConclusionsFacebook contains useful information about IPF, but posts with misinformation and less guideline content have higher user engagement, making them more visible. Identifying ways to help patients with IPF discriminate between useful and harmful information on Facebook and other social media platforms is an important task for health care professionals. 相似文献
105.
Xue Yang Benjamin H K Yip Arthur D P Mak Dexing Zhang Eric K P Lee Samuel Y S Wong 《JMIR Public Health and Surveillance》2021,7(5)
BackgroundSocial media has become a ubiquitous part of daily life during the COVID-19 pandemic isolation. However, the role of social media use in depression and suicidal ideation of the general public remains unclear. Related empirical studies were limited and reported inconsistent findings. Little is known about the potential underlying mechanisms that may illustrate the relationship between social media use and depression and suicidal ideation during the COVID-19 pandemic.ObjectiveThis study tested the mediation effects of social loneliness and posttraumatic stress disorder (PTSD) symptoms on the relationship between social media use and depressive symptoms and suicidal ideation, as well as the moderation effect of age on the mediation models.MethodsWe administered a population-based random telephone survey in May and June 2020, when infection control measures were being vigorously implemented in Hong Kong. A total of 1070 adults (658 social media users and 412 nonusers) completed the survey. Structural equation modeling (SEM) and multigroup SEM were conducted to test the mediation and moderation effects.ResultsThe weighted prevalence of probable depression was 11.6%; 1.6% had suicidal ideation in the past 2 weeks. Both moderated mediation models of depressive symptoms (χ262=335.3; P<.05; comparative fit index [CFI]=0.94; nonnormed fit index [NNFI]=0.92; root mean square error of approximation [RMSEA]=0.06) and suicidal ideation (χ234=50.8; P<.05; CFI=0.99; NNFI=0.99; RMSEA=0.02) showed acceptable model fit. There was a significantly negative direct effect of social media use on depressive symptoms among older people (β=–.07; P=.04) but not among younger people (β=.04; P=.55). The indirect effect via PTSD symptoms was significantly positive among both younger people (β=.09; P=.02) and older people (β=.10; P=.01). The indirect effect via social loneliness was significant among older people (β=–.01; P=.04) but not among younger people (β=.01; P=.31). The direct effect of social media use on suicidal ideation was not statistically significant in either age group (P>.05). The indirect effects via PTSD symptoms were statistically significant among younger people (β=.02; P=.04) and older people (β=.03; P=.01). Social loneliness was not a significant mediator between social media use and suicidal ideation among either age group (P>.05).ConclusionsSocial media may be a “double-edged sword” for psychosocial well-being during the COVID-19 pandemic, and its roles vary across age groups. The mediators identified in this study can be addressed by psychological interventions to prevent severe mental health problems during and after the COVID-19 pandemic. 相似文献
106.
107.
【目的】 探析医学科技期刊新媒体爆款文章的特征及生成策略。 【方法】 以《协和医学杂志》为例,筛选出其在今日头条平台2018年10月至2020年12月阅读量为“10万+”的爆款文章,分析文章特征,并从资源挖掘、内容生产及推广传播环节提出有效策略。 【结果】 医学科技期刊新媒体爆款文章具有话题热、标题靓、排版精、互动深的特点;借力平台优势、融合科普定位、发挥“意见领袖”作用、巧搭新闻热点事件、精心设计版式以及多网媒滚筒式传播均为医学科技期刊新媒体爆款文章生成的有力之举。 【结论】 医学科技期刊新媒体深挖优势资源,把好内容及传播环节,策略性运营,可为爆款文章生成提供保障,进而提升期刊品牌影响力和新媒体综合实力。 相似文献
108.
PurposeTexting is used by many adolescents and has the potential to improve well-being, as youth can reach out for support immediately after experiencing a stressful situation. Many studies have examined whether texting is associated with well-being, but few have used experimental designs, preventing causal claims.MethodsIn this experimental study, 130 adolescents (Mage = 12.41) participated with a same-gender friend whom they texted regularly. Both adolescents completed a task that elicited stress and then engaged in one of the following randomly assigned activities: texting their friend, watching a video on a cellphone (passive-phone condition), or sitting quietly (no activity condition). Participants reported their mood and stress levels after the stress task and again after the activity. Heart rate variability was measured throughout.ResultsParticipants who texted their friend reported higher moods (b = ?.80, standard error [SE] = .24, p < .001, ηp2 = .09) and lower stress at the end of the study than those in the no activity condition (b = .51, SE = .25, p = .046, ηp2 = .04) and higher moods than adolescents in the passive-phone condition (b = ?.74, SE = .25, p = .004, ηp2 = .08). No differences were noted between the passive-phone and no activity conditions. There were no differences in heart rate variability between the three conditions. The effects of texting on mood, self-reported stress, and heart rate variability did not differ by gender.ConclusionsBoth boys and girls may benefit from texting a friend after experiencing a stressful event. 相似文献
109.
110.
目的:寻求既经济又有效的造血生长因子样活性物质。方法:采用造血祖细胞体外培养与造血生长因子生物活性检测等实验血液学技术,检测胎肌培养上清液、骨液基质细胞培养上清液、胸腺细胞培养上清液与脾细胞培养上清液对造血祖细胞CFU-GM、BFU-E和CFU-Mix增殖分化的影响。结果胎肌培养上清液和对CFU-GM和CFU-Mix的体外地产殖与分化有明显刺激作用。而胸腺与脾细胞条件培养上清液对BFU-E的生长有显著促进作用。结论:胎肌培养上清液中可能含GM-CSF样活性物质。而胸腺与脾细胞培养上清液具有较高IL-3样活性,可以利用组织与细胞培养上清液替代重组造血生长因子进行造血细胞的实验研究和临床诊断。 相似文献