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2021 ◽  
Author(s):  
Esther Kissling ◽  
Mariëtte Hooiveld ◽  
Iván Martínez-Baz ◽  
Clara Mazagatos ◽  
Naoma William ◽  
...  

IntroductionIn July and August 2021, the SARS-CoV-2 Delta variant dominated in Europe. We measured COVID-19 vaccine effectiveness (VE) against symptomatic infection, using a multicentre test-negative study at primary care/community level in Europe.MethodsPatients presenting with COVID-19/ARI symptoms at primary care/community level in 10 countries were tested for SARS-CoV-2. We measured complete primary course overall VE among those aged 30–44, 45–59, 60–74 and ≥75 years, and among those 30–59 and ≥60 years by vaccine brand and by time since vaccination.ResultsOverall VE was 74% (95%CI: 69–79), 76% (95%CI: 71–80), 63% (95%CI: 48–75), 63% (95%CI: 16–83) among those aged 30–44, 45–59, 60–74 and ≥75 years, respectively. VE among those aged 30–59 years was 78% (95%CI: 75–81), 66% (95%CI: 58–73), 91% (95%CI: 87–94) and 52% (95%CI: 40–61), for Comirnaty, Vaxzevria, Spikevax and COVID-19 Vaccine Janssen, respectively. VE among those aged ≥60 years was 67% (95%CI: 52–77), 65% (95%CI: 48–76), 83% (95%CI: 64–92) for Comirnaty, Vaxzevria and Spikevax, respectively. Comirnaty VE among those aged 30–59 years was 87% (95%CI: 83–89) and 65% (95%CI: 56–71%) at 14–29 days and ≥90 days between vaccination and onset of symptoms, respectively.ConclusionsVE against the symptomatic SARS-CoV-2 Delta variant infection varied among brands, ranging from 52–91%. While some waning of the vaccine effect may be present (sample size limited this analysis to only Comirnaty), protection was 65% ≥90 days between vaccination and onset.


2021 ◽  
Author(s):  
Otavio T Ranzani ◽  
Rogério dos Santos Leite ◽  
Larissa Domingues Castilho ◽  
Crhistinne Cavalheiro Maymone Gonçalves ◽  
Geraldo Resende ◽  
...  

We used a test-negative design to estimate the vaccine effectiveness of Ad26.COV2.S (Janssen) against symptomatic COVID-19 and clinical outcomes in Mato-Grosso do Sul, Brazil. We analyzed 11,817 RT-PCR tests. The mean age was 37 (SD=17) years, 2,308 (20%) of individuals more or equal than 50 years and almost two-thirds of the population was Brown/Pardo. Adjusted effectiveness against symptomatic COVID-19 after 28 days of the single dose was 50.9% (95% CI, 35.5-63.0). Adjusted effectiveness against clinical outcomes was 72.9% (95% CI, 35.1-91.1) for hospitalization, 92.5% (95% CI, 54.9-99.6) for ICU admission, 88.7% (95% CI, 17.9-99.5) for mechanical ventilation and 90.5% (95% CI, 31.5-99.6) for death. Despite lacking precision on some estimates, a single dose of Ad26.COV2.S vaccine continues to protect specially for severe forms of COVID-19 in the context of new variants.


2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Xin Sun ◽  
Shaylene Nancekivell ◽  
Susan A. Gelman ◽  
Priti Shah

AbstractChinese students are more likely than US students to hold a malleable view of success in school, yet are more likely to hold fixed mindsets about intelligence. We demonstrate that this apparently contradictory pattern of cross-cultural differences holds true across multiple samples and is related to how students conceptualize intelligence and its relationship with academic achievement. Study 1 (N > 15,000) confirmed that US students endorsed more growth mindsets than Chinese students. Importantly, US students’ mathematics grades were positively related to growth mindsets with a medium-to-large effect, but for Chinese students, this association was slightly negative. Study 2 conceptually replicated Study 1 findings with US and Chinese college samples, and further discovered that cross-cultural differences in intelligence mindset beliefs corresponded to how students defined intelligence. Together, these studies demonstrated systematic cross-cultural differences in intelligence mindset and suggest that intelligence mindsets are not necessarily associated with academic motivation or success in the same way across cultures.


2020 ◽  
Vol 10 (22) ◽  
pp. 8188
Author(s):  
Benjamin Aziz ◽  
Jeyong Jung ◽  
Julak Lee ◽  
Yong-Tae Chun

In this study, we evaluated one of the modern automated steganalysis tools, Stegdetect, to study its false negative rates when analysing a bulk of images. In so doing, we used JPHide method to embed a randomly generated messages into 2000 JPEG images. The aim of this study is to help digital forensics analysts during their investigations by means of providing an idea of the false negative rates of Stegdetect. This study found that (1) the false negative rates depended largely on the tool’s sensitivity values, (2) the tool had a high false negative rate between the sensitivity values from 0.1 to 3.4 and (3) the best sensitivity value for detection of JPHide method was 6.2. It is therefore recommended that when analysing a huge bulk of images forensic analysts need to take into consideration sensitivity values to reduce the false negative rates of Stegdetect.


2020 ◽  
Author(s):  
Erin Corwin Westgate ◽  
Timothy D. Wilson ◽  
Nick Buttrick ◽  
Remy Furrer

When left to their own devices, people could choose to enjoy their own thoughts. But recent work suggests they don’t. When given the freedom, people do not spontaneously choose to think for pleasure, and when directed to do so, struggle to concentrate successfully. And, people find it somewhat boring and much less enjoyable than other solitary activities. One reason for this is that people may not know how to think for pleasure. Specifically, they may not know what to think about to make this both a meaningful and pleasant experience. We tested this prediction in two preregistered studies, by providing specific examples of meaningful topics (Study 1) or instructing participants to think “meaningful” thoughts (Study 2). Although providing specific examples of meaningful topics boosted how meaningful and enjoyable people found thinking for pleasure (Study 1), asking people to think “meaningful” thoughts (as compared to pleasurable ones) did not, because some of the meaningful topics people thought about were negative (Study 2). In order for thinking for pleasure to be pleasurable, people need to focus on topics that are both meaningful and positive.


Blood ◽  
2020 ◽  
Vol 135 (16) ◽  
pp. 1307-1308
Author(s):  
Scott M. Stevens

Recurrent ipsilateral deep vein thrombosis has major clinical ramifications, but is often difficult to distinguish from residual clot by ultrasound. van Dam et al demonstrated that magnetic resonance direct thrombus imaging can accurately distinguish the two, with a low risk of venous thromboembolism recurrence after a negative study.


2020 ◽  
Vol 25 (1) ◽  
Author(s):  
Jeffrey C Kwong ◽  
Hannah Chung ◽  
James KH Jung ◽  
Sarah A Buchan ◽  
Aaron Campigotto ◽  
...  

Introduction Annual influenza vaccination is recommended for older adults, but evidence regarding the impact of repeated vaccination has been inconclusive. Aim We investigated vaccine effectiveness (VE) against laboratory-confirmed influenza and the impact of repeated vaccination over 10 previous seasons on current season VE among older adults. Methods We conducted an observational test-negative study in community-dwelling adults aged > 65 years in Ontario, Canada for the 2010/11 to 2015/16 seasons by linking laboratory and health administrative data. We estimated VE using multivariable logistic regression. We assessed the impact of repeated vaccination by stratifying by previous vaccination history. Results We included 58,304 testing episodes for respiratory viruses, with 11,496 (20%) testing positive for influenza and 31,004 (53%) vaccinated. Adjusted VE against laboratory-confirmed influenza for the six seasons combined was 21% (95% confidence interval (CI): 18 to 24%). Patients who were vaccinated in the current season, but had received no vaccinations in the previous 10 seasons, had higher current season VE (34%; 95%CI: 9 to 52%) than patients who had received 1–3 (26%; 95%CI: 13 to 37%), 4–6 (24%; 95%CI: 15 to 33%), 7–8 (13%; 95%CI: 2 to 22%), or 9–10 (7%; 95%CI: −4 to 16%) vaccinations (trend test p = 0.001). All estimates were higher after correcting for misclassification of current season vaccination status. For patients who were not vaccinated in the current season, residual protection rose significantly with increasing numbers of vaccinations received previously. Conclusions Although VE appeared to decrease with increasing numbers of previous vaccinations, current season vaccination likely provides some protection against influenza regardless of the number of vaccinations received over the previous 10 influenza seasons.


2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Panu Wetwittayakhlang ◽  
Jirapat Wonglhow ◽  
Nisa Netinatsunton ◽  
Naichaya Chamroonkul ◽  
Teerha Piratvisuth

Abstract Background Capsule endoscopy (CE) is the preferred diagnostic test of choice in the investigation of obscure gastrointestinal bleeding (OGIB). Although, a conservative strategy is recommended in the short-term, for cases with a negative result from CE, the impact of CE on long-term re-bleeding still remains unclear. Hence, the aim of this study was to determine the long-term re-bleeding rate along with predictors after CE in patients with OGIB. Methods We retrospectively reviewed 216 patients with OGIB, whom had received a CE examination, so as to investigate the cause of obscure GI bleeding; between July 2008 and March 2018. The patient’s characteristics, medication use, CE finding, treatments strategy, re-bleeding episodes and follow-up information were collected from the institutional electronic medical chart and CE database. Re-bleeding free survival was evaluated using Kaplan-Meier curves with log rank test, whilst predictors associated with the re-bleeding episodes were analyzed via the use of Cox proportional hazard model. Results One hundred and thirty-three patients with OGIB, having received CE were enrolled in the analysis. The pool rate of re-bleeding was 26.3% (35/133) during a follow-up duration of 26 months after CE. Patients with positive CE study, without specific treatment, had higher rates of re-bleeding (47.6%) than those with positive study whom received specific treatment (25.7%), and negative study (20.8%) (p = 0.042). Although, the re-bleeding free survival was not significantly different among the groups (log rank test; P = 0.10). Re-bleeding events occurring within 6, 12, and 24 months after CE were 36, 64 and 92%, respectively. The high-frequency re-bleeding etiologies were the small bowel angiodysplasias and abnormal vascular lesions. Furthermore, independent predictors for re-bleeding after CE were patients with cirrhosis (hazard ratio, HR 4.06), incomplete CE visualization (HR 2.97), and a history of previous GI bleeding (HR 2.80). Conclusions The likelihood of re-bleeding after CE was higher in patients with positive CE study than those with negative study. Specific treatments, or therapeutic interventions for patients with detectable lesions reduced the probability of re-bleeding episodes in long-term follow-up. Close follow-up for recurrent bleeding is recommeded for at least 2 years after CE.


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