June July Research Articles

Psychological distress and suicidality in psychiatric patients during the COVID-19 pandemic in Norway: A repeated cross-sectional study

BackgroundPsychiatric patients are vulnerable to disruptions caused by the Corona Virus Disease 2019 (COVID-19) pandemic. This study aimed to investigate the effects of the pandemic on mental health symptoms and suicidality among these patients during lockdowns. MethodsThis repeated cross-sectional study utilized data from “Psychological distress and Coping in Patients in Community Mental Health Centers during COVID-19 pandemic (PsyCo-COVID-19) " study, conducted in two phases between June–July 2020 and March–April 2021. It included 261 participants from six Community Mental Health Centers (CMHCs) who completed a digital questionnaire, including Norwegian version of Mini International Neuropsychiatric Interview Plus (M.I.N.I. Plus), Hopkins Symptoms Checklist (HSCL-25), Post-traumatic Stress Disorder Checklist (PCL-5). ResultsA higher percentage of patients reported PTSD during the second phase of lockdown (47.4%) compared to the first phase of lockdown (33.7%). A third of participants (33.7%) reported high levels of suicidality. Moderate to severe effects of pandemic on mental health were associated with a significantly higher risk of suicide (AOR = 3.12; 95% CI: 1.50, 6.48; p = 0.0001), while having children (AOR = 0.35; 95% CI: 0.16, 0.76; p = 0.008) and being employed (AOR = 0.44; 95% CI: 0.23, 0.84; p = 0.013) were protective factors. Non-Norwegian background was associated with a higher risk of suicide (AOR = 2.59; 95% CI: 1.08, 6.19; p = 0.032). ConclusionHigh prevalence of suicidality was found among patients in CMHCs in Norway, with a significant association with self-reported worsening of mental health. PTSD and suicidality increased significantly during the second phase of lockdown, emphasizing the lasting impact of the pandemic on mental health. Targeted interventions and support services are needed for psychiatric patients during times of increased stress and uncertainty. Healthcare providers should be aware of the increased risk of suicide and provide appropriate support and interventions to prevent adverse outcomes.

Summertime response of ozone and fine particulate matter to mixing layer meteorology over the North China Plain

Abstract. Measurements of surface ozone (O3), PM2.5 and its major secondary components (SO42-, NO3-, NH4+, and organic carbon (OC)), mixing layer height (MLH), and other meteorological parameters were made in the North China Plain (NCP) during the warm season (June–July) in 2021. The observation results showed that the summertime regional maximum daily 8 h average ozone (MDA8 O3) initially increased and reached the maximum value (195.88 µg m−3) when the MLH ranged from approximately 900 to 1800 m, after which the concentration of O3 decreased with further increase in MLH. Interestingly, synchronous increases in PM2.5 concentration along with the development of the mixing layer (MLH <1200 m) were observed, and the positive response of PM2.5 to MLH was significantly associated with the increase in SO42- and OC. It was found that this increasing trend of PM2.5 with elevated MLH was driven not only by the wet deposition process but also by the enhanced secondary chemical formation, which was related to appropriate meteorological conditions (50 % < RH <70 %) and increased availability of atmospheric oxidants. Air temperature played a minor role in the change characteristics of PM2.5 concentration, but it greatly controlled the different change characteristics of SO42- and NO3-. The concentrations of PM2.5, its major secondary components, and the oxidation ratios of sulfate (SOR) and nitrate (NOR) increased synchronously with elevated MDA8 O3 concentrations, and the initial increase in PM2.5 along with increased MLH corresponded well with that of MDA8 O3. We highlight that the correlation between MLH and secondary air pollutants should be treated with care in hot weather, and the superposition-composite effects of PM2.5 and O3 along with the evolution of mixing layer should be considered when developing PM2.5–O3 coordinated control strategies.

Future weakening of southeastern tropical Atlantic Ocean interannual sea surface temperature variability in a global climate model

AbstractFuture changes in the southeastern tropical Atlantic interannual sea surface temperature (SST) variability in response to increasing greenhouse gas concentrations are investigated utilizing the global climate model FOCI. In that model, the Coastal Angola Benguela Area (CABA) is among the regions of the tropical Atlantic that exhibits the largest surface warming. Under the worst-case scenario of the Shared Socioeconomic Pathway 5-8.5 (SSP5-8.5), the SST variability in the CABA decreases by about 19% in 2070–2099 relative to 1981–2010 during the model’s peak interannual variability season May–June–July (MJJ). The weakening of the MJJ interannual temperature variability spans the upper 40 m of the ocean along the Angolan and Namibian coasts. The reduction in variability appears to be related to a diminished surface-layer temperature response to thermocline-depth variations, i.e., a weaker thermocline feedback, which is linked to changes in the mean vertical temperature gradient. Despite improvements made by embedding a high-resolution nest in the ocean a significant SST bias remains, which might have implications for the results.

Contrasting the Impacts of Intraseasonal Oscillations on Yangtze Precipitation during the Summer of 1998 and 2016

In 1998 and 2016, boreal summer intraseasonal oscillation (BSISO) could reach the middle-lower reaches of the Yangtze River basin (YRB), leading to extreme precipitation. Based on multiple daily data, this study reveals the differences in BSISO events and mechanisms between 1998 and 2016. In June–July of 1998 (2016), YRB precipitation was impacted by 30–60-day oscillation, i.e., BSISO1 (10–30-day oscillation, i.e., BSISO2), with two strong (three) precipitation events occurring. In 1998, when BSISO1 was in phases 1–4 (phases 5–8), the YRB experienced a wet (dry) episode. In 2016, when BSISO2 was in phases 1–2 and 7–8 (phases 3–6), the YRB experienced a wet (dry) episode. In 1998, in event 1, the active convection of the YRB first originated in the South China Sea–western Pacific (SCS–WP) and then in the tropical Indian Ocean (IO). In 1998, in event 2, the active convection of the YRB originated in the SCS–WP. In 2016, in events 1 and 3, the active convection of the YRB originated from the SCS–WP. In 2016, in event 2, the active convection of the YRB originated from the tropical IO and the extratropical WP. Different SST and atmospheric circulations explain different BSISO modes that dominate in the YRB. In 1998 (2016), in summer, (no) strong easterly wind anomalies occurred in the SCS–WP, which are favorable (unfavorable) for the enhancement of BSISO1. Accompanying the suppressed BSISO1, BSISO2 was enhanced in 2016.

Long-Term Trends and Sociodemographic Inequalities of Emotional/Behavioral Problems and Poor Help-Seeking in Adolescents During the COVID-19 Pandemic

PurposeDuring the first 3 years of the coronavirus disease (COVID-19) pandemic, we investigated the long-term trends of emotional/behavioral problems and poor help-seeking behavior in adolescents and examined the sociodemographic inequalities in these trends. MethodsA multiwave cross-sectional survey was conducted in Japan from October–November 2020, June–July 2021, and June–July 2022 using an anonymous questionnaire. Trends of emotional/behavioral problems (e.g., emotional symptoms, hyperactivity/inattention, and total difficulties) and poor help-seeking were tested using a chi-squared test with Bonferroni correction. The effects of sociodemographic factors (grade, gender, country of origin, and number of parents) on emotional/behavioral problems and poor help-seeking were examined by two mixed-effect logistic regression models: (1) with fixed effects for years and sociodemographic factors and (2) stratified by years if the interaction terms between years and each sociodemographic factor were significant. ResultsThe prevalence of total difficulties and emotional symptoms was the highest in 2021. The number of adolescents reporting hyperactivity/inattention and poor help-seeking increased between 2020 and 2021 and remained high in 2022. Inequalities in emotional/behavioral problems and poor help-seeking behavior were found with respect to all sociodemographic factors. DiscussionDespite the persistent emotional/behavioral problems, the results suggested that the number of adolescents who were unable to seek help increased during the COVID-19 pandemic. Additionally, heterogeneities in the trends with respect to grade, gender, country of origin, and number of parents were detected. Prioritized supports targeting those with sociodemographic disadvantages may be needed to mitigate these inequalities in response to the pandemic.

Blood donation practices, processing and utilisation of blood components in government tertiary hospitals in Nigeria: a multicentre cooperative study.

Timely access to safe blood and blood components is still a challenge in Nigeria. This study aimed to determine blood donation practices, processing and utilization of blood components across government tertiary hospitals (THs) in Nigeria. This was a descriptive cross-sectional study done in Nigeria in June-July 2020. Data were analysed with SPSS version 21.0. Data were collected from 50 THs. The majority (68%) of the THs lack facilities for blood component preparation and only 18% and 32% provide cryoprecipitate and platelet concentrate, respectively. Whole blood was most commonly requested (57.04%). All facilities tested blood for HIV, HBV and HCV, but the majority (23 [46%]) employed rapid screening tests alone and nucleic acid testing was not available in any hospitals. The manual method was the most common method of compatibility testing in 90% (45/50) and none of the THs routinely perform extended red cell typing. The average time to process routine, emergency and uncross-matched requests were a mean of 109.58±79.76min (range 45.00-360.00), 41.62±25.23 (10.00-240.00) and 11.09±4.92 (2.00-20.00), respectively. Facilities for blood component preparation were not widely available. Concerned government authorities should provide facilities for blood component preparation.

Machine-Learning-Based Precipitation Reconstructions: A Study on Slovenia’s Sava River Basin

The Sava River Basin (SRB) includes six countries (Slovenia, Croatia, Bosnia and Herzegovina, Serbia, Albania, and Montenegro), with the Sava River (SR) being a major tributary of the Danube River. The SR originates in the mountains (European Alps) of Slovenia and, because of a recent Slovenian government initiative to increase clean, sustainable energy, multiple hydropower facilities have been constructed within the past ~20 years. Given the importance of this river system for varying demands, including hydropower (energy production), information about past (paleo) dry (drought) and wet (pluvial) periods would provide important information to water managers and planners. Recent research applying traditional regression techniques and methods developed skillful reconstructions of seasonal (April–May–June–July–August–September or AMJJAS) streamflow using tree-ring-based proxies. The current research intends to expand upon these recent research efforts and investigate developing reconstructions of seasonal (AMJJAS) precipitation applying novel Artificial Intelligence (AI), Machine Learning (ML), and Deep Learning (DL) techniques. When comparing the reconstructed AMJJAS precipitation datasets, the AI/ML/DL techniques statistically outperformed traditional regression techniques. When comparing the SRB AMJJAS precipitation reconstruction developed in this research to the SRB AMJJAS streamflow reconstruction developed in previous research, the temporal variability of the two reconstructions compared favorably. However, pluvial magnitudes of extreme periods differed, while drought magnitudes of extreme periods were similar, confirming drought is likely better captured in tree-ring-based proxy reconstructions of hydrologic variables.

Sea–air coupling leads to a decrease in precipitation in East Asia under present day conditions that is partially alleviated in future simulations

The offshore region of East Asia has a crucial role in recycling precipitation, especially in the current context of a warming climate. This is because the atmospheric feedback from the sea offshore East Asia directly impacts and modifies precipitation patterns by influencing the seasonal cycles of the surface energy and water budgets. We used a regional climate model incorporating sea–air coupling to investigate and better understand these climate feedback mechanisms in East Asia. We identified a reduction in precipitation caused by sea-air coupling over East Asia during the time period 1991 − 2014 under present day conditions. Specifically, we observed an average decrease in precipitation of about 0.1 ± 0.40 mm day−1 during June–July–August. This decrease in precipitation can be attributed to a combination of factors, including the effects of upward solar radiation, the asymmetry of the thermal contrast between the land and the sea, decreased evaporation in the southeastern ocean and the weakened transport of water vapor from the sea to the land. Our research suggests that the decrease triggered by sea–air coupling will be partially alleviated under future conditions, although not completely reversed, in terms of its impact on precipitation in eastern China. Although some relief is anticipated, the overall influence of sea–air coupling on patterns of precipitation in East Asia will persist, especially south of the Yellow River in eastern China.

Ocean-atmosphere heat exchange seasonal cycle on the West Florida Shelf derived from long term moored data

Twenty-three years of surface meteorological and oceanographic data sampled from moored buoys are used to study the seasonal and interannual variations of ocean–atmosphere heat exchange and its influence on West Florida Continental Shelf (WFS) water temperature and stratification. The data are from the University of South Florida's Coastal Ocean Monitoring and Prediction System (COMPS), part of the Southeast Coastal Ocean Observing Regional Association (SECOORA). Observed are incoming short and longwave radiation, air and sea surface temperatures (AT and SST), barometric pressure, relative humidity, wind velocity, water column velocity profiles, and water column temperature at discrete depths. These data are used to estimate net shortwave and longwave radiation and sensible and latent heat fluxes via the COARE 3.6 algorithm. When combined, these radiative and turbulent heat flux influences are compared with the heating and cooling of the WFS water column and SST. On seasonal average, heating starts in February and lasts through August, with a maximum rate of change in May, while cooling starts in September and lasts through January, with the maximum rate of change in October. Also on seasonal average, SST varies from 18.4 °C in February to 30.4 °C in August at mooring C10 (at the 25 m isobath) and from 20.1 °C in February to 30.2 °C in August at mooring C12 (at the 50 m isobath), the differences in the seasonal range being due to increased ocean circulation influence in deeper water. Both the spring and fall transition onsets, February and August, respectively, occur when the sign of the net heat flux changes. The water column begins to stratify in March, peaking in June–July and lagging the surface heating by one or two months, then decreasing through September at C10 and October at C12. Stratification is also modified by persistent upwelling when the Gulf of Mexico Loop Current (LC) interacts with the WFS slope at its southwest corner near the Dry Tortugas. Interannual temperature anomalies from the seasonal cycle are also related to how the LC interacts with the WFS slope.

Future projections of extreme precipitation in Tropical America and Panama under global warming based on 150‐year continuous simulations using 20‐km and 60‐km atmospheric general circulation models

AbstractThis study explores future changes in extreme precipitation across tropical America and Panama using 150‐year continuous experiments run on the Meteorological Research Institute atmospheric general circulation model at horizontal resolutions of 20 km (AGCM20) and 60 km (AGCM60). Tropical America is a warming hotspot where the mean seasonal precipitation amounts are decreasing, but annual maximum daily precipitation amounts are following an increasing trend. In Panama, future climates simulated using AGCM20 and AGCM60 show an increase in December–January–February (DJF) precipitation over eastern Panama, and a decrease in June–July–August (JJA) precipitation over western areas near the Pacific coast. Annual maximum daily precipitation increases on the eastern side of the country in both models. The mean annual maximum daily precipitation for tropical America shows decadal oscillations, similar to the global mean but with smaller amplitude variations. The mean annual maximum daily precipitation for Panama shows large oscillations, even for the 10‐year running mean. For tropical America, the mean annual maximum daily precipitation has a linear relationship with surface air temperature that is independent of the Representative Concentration Pathway scenarios, but this is not the case for Panama. Temporal correlations between the tropical America mean annual maximum daily precipitation and annual mean surface air temperature in the historical experiments have a geographical distribution similar to that of the sea surface temperature anomalies during negative El Niño/Southern Oscillation events, but not in the future experiments. The correlation between the Panama mean annual maximum daily precipitation and surface air temperature in both the historical and future experiments has a geographical distribution similar to that of the temporal correlation for the tropical America mean in the historical experiment. The annual maximum daily precipitation in Panama is projected to increase during negative El Niño events in the future, as observed in the historical climate.

A NEST OF CLUB-WINGED MANAKIN MACHAEROPTERUS DELICIOSUS IN NORTHWEST ECUADOR

The Club-winged Manakin Machaeropterus deliciosus is an iconic Pipridae species due to its display behavior, including unique mechanical sounds produced by vibrating modified wing feathers. However, its nesting biology remains poorly known. We present a detailed description of one nest studied in northwest Ecuador in June–July 2021. We provide new information on incubation and maternal care. The nest was a low cup/fork sited on three forks, covered with moss, built 90 cm above the ground and at 50 m distance from a lekking site. The female had high nest attentiveness during the incubation period but decreased markedly in the first nine days post-hatching. The nest produced two juveniles that fledged 16 days after hatching. The breeding biology of this species remains poorly studied, so we recommend further research, including protracted monitoring of nests to understand important aspects of M. deliciosus breeding biology, including incubation period, attendance rates, and nesting success.

Psychosocial predictors of distress in East and West Germans during the COVID-19 pandemic

Background Psychological (meaning in life, science attitude, internal locus of control, religiosity), and social factors (social support, cohesion) can counteract stressor-related distress. We investigated these factors’ links with peri-pandemic distress (depression, anxiety, intrusions) and whether they weakened the impact of being affected by the COVID-19 pandemic. We compared prior East and West Germans on predictors and distress to investigate if their different backgrounds created lasting differences. Methods A population-representative German sample aged 45 to 70 (N = 380) in terms of age, sex, and school education completed online questionnaires in May–July 2020 and June–July 2021. We examined the predictive relations with correlation, forward inclusion regression, and moderation analyses. Results Social support predicted lower distress, also prospectively. Meaning in life predicted lower distress cross-sectionally. Religiosity predicted greater distress. Life meaning and social support partly weakened the link between being affected by the pandemic and distress, religiosity and science attitude strengthened this link. The only significant East/West difference was in religiosity, which was higher in the West. Conclusion Social resources appeared particularly important in adjusting to the pandemic. The identified predictors may inform interventions. East and West Germans’ similarity might indicate that their post-war separation did not create lasting differences in the investigated factors.

Seasonal Snowpack Microbial Ecology and Biogeochemistry on a High Arctic Ice Cap Reveals Negligible Autotrophic Activity During Spring and Summer Melt

AbstractSnowpack ecosystem studies are primarily derived from research on snow‐on‐soil ecosystems. Greater research attention needs to be directed to the study of glacial snow covers as most snow cover lies on glaciers and ice sheets. With rising temperatures, snowpacks are getting wetter, which can potentially give rise to biologically productive snowpacks. The present study set out to determine the linkage between the thermal evolution of a snowpack and the seasonal microbial ecology of snow. We present the first comprehensive study of the seasonal microbial activity and biogeochemistry within a melting glacial snowpack on a High Arctic ice cap, Foxfonna, in Svalbard. Nutrients from winter atmospheric bulk deposition were supplemented by dust fertilization and weathering processes. NH4+ and PO43− resources in the snow therefore reached their highest values during late June and early July, at 22 and 13.9 mg m−2, respectively. However, primary production did not respond to this nutrient resource due to an absence of autotrophs in the snowpack. The average autotrophic abundance on the ice cap throughout the melt season was 0.5 ± 2.7 cells mL−1. Instead, the microbial cell abundance was dominated by bacterial cells that increased from an average of (39 ± 19 cells mL−1) in June to (363 ± 595 cells mL−1) in early July. Thus, the total seasonal biological production on Foxfonna was estimated at 153 mg C m−2, and the glacial snowpack microbial ecosystem was identified as net‐heterotrophic. This work presents a seasonal “album” documenting the bacterial ecology of glacial snowpacks.

Baltic Sea Research on Cruise 61 of the R/V Akademik Ioffe (June–July 2022)

Baltic Sea Research on Cruise 61 of the R/V Akademik Ioffe (June–July 2022)

Noise levels in a changing Arctic Ocean and its implications for security

Arctic Ocean is undergoing an “Atlantification” of its oceanographic properties. Sea ice retreat and reduction of sea ice age will affect its underwater soundscape, with anthropogenic noise expected to increase due to the exploitation of new maritime routes. The CMRE’s Environmental and Operational Effectiveness Programme conducted a study of the new Arctic oceanographic conditions and ambient noise by deploying in 2021 and in 2022 different moorings equipped with passive acoustic recorders and oceanographic sensors. Data did not show a clear relation between sea-ice concentration and noise levels in the marginal ice zone. However, noise levels indicate that the possible presence of transmissions ducts might increase high frequency noise in the subsurface area. Seasonality and variations in the overall soundscapes were also evident by the presence of sounds from biological sources. In 2023, with the support of the NATO Office of the Chief Scientist, CMRE started a long-term scientific endeavor to study how climate change might affect the Alliance’s security in the maritime domain. A significant research effort is focused on the Arctic, and in June–July 2023 CMRE deployed three deep moorings for monitoring the acoustic-oceanographic conditions in the long term. [Work supported by the NATO Allied Command Transformation.]

Asian dust-deposition flux to the subarctic Pacific estimated using single quartz particles

Iron availability limits marine ecosystem activities in large areas of the ocean. However, the sources and seasonal supply of iron, critically important for controlling surface ocean biogeochemistry and carbon cycling, are poorly understood. The western subarctic Pacific is a high-nutrient and low-chlorophyll region, and despite high concentrations of macronutrients, iron limits phytoplankton production in summer. Here, we determine the seasonal deposition flux of Asian dust using scanning electron microscope–cathodoluminescence analysis of single quartz particles derived from the western subarctic Pacific during 2003–2022 to trace provenance. We found a high (up to 6.9 mg m−2 day−1) deposition flux of Asian dust in May, June, and early July, with an annual average of 1.0 ± 0.2 mg m−2 day−1. The supply of dissolved-iron flux calculated from Asian dust was 0.9 ± 0.3 µg m−2 day−1 during the high productivity season (April–July), which is approximately half that from the deeper part of the ocean, calculated from vertical profiles of dissolved iron. Our study provides a reliable approach for estimating iron supply from dust to the surface ocean that may be critical for sustaining biological productivity under future ocean stratification, which suppresses nutrient supply from the subsurface ocean.

Period and length of high surface gravity waves measured in the coastal waters of eastern Arabian Sea and its variations in 10 years

Information on the period and length of waves is required for the planning and design of marine facilities and wave energy converters. In this article, the period and length of the waves measured during the peak monsoon (June–July) in the coastal waters of the eastern Arabian Sea for 10 years are examined. The most typical wave periods (T) are within 3.9 s and 5.5 s and about 25 % are above 9 s. The peak wave period (Tp) indicates that during the peak monsoon months, long-period waves dominate the eastern Arabian Sea. Significant wave period and integral wave period show a good linear relationship with energy wave period with a slope value close to 1. There are inter-annual variations of up to 15 % in the 90-percentile value of the Tp. From 2010 to 2019, the average wavelength during peak monsoon varied from 61.3 m to 67.6 m and the maximum wavelength from 216.6 m to 248.8 m. Interannual variations in the 90-percentile values for wavelength corresponding to maximum wave height is only 7 %.

Doğum Sonu Kanama Yönetiminde Ebelerin Bilgi ve Becerilerini Geliştirmek İçin Yerinde Simülasyon Kullanimi: Amasya- Şanlıurfa Örneği

Postpartum hemorrhage has a primary and important place in the pre- and post-graduate education of midwives, who are primarily responsible for maternal health. This research aims to develop the knowledge and skills of midwifes in obstetrics units through simulation method in postpartum haemorrhage management. 
 The research is in a quasi-experimental, single-group pre-test and post-test design. A training included 28 midwives who agreed to participate in the research between June 1st and July 14th. This educational intervention lasted for 24 hours and included theoretical, skills training and skills training accompanied by scenarios, and it was designed to be given in the hospital. Gathered data were evaluated through SPSS package software. 
 Knowledge and skills before and after the educational intervention, and Self-Confidence/Efficiency Scale scores in Patient Intervention were found to be statistically significant. An increase in all scores before and after the educational intervention was observed. When these two hospitals were compared, some differences emerged.
 Simulation improves both knowledge and skills even for a difficult subject such as postpartum hemorrhage, but there are differences between hospitals due to differences in practice. This may mean that we need to share our experiences more with each other.

Weather pattern conducive to the extreme summer heat in North China and driven by atmospheric teleconnections

Extreme summer heat can have severe socioeconomic impacts and has occurred frequently in North China in recent years, most notably in June–July 2023, when North China experienced the most widespread, persistent, and high-intensity extreme heat on record. Here, typical weather patterns covering North China and its surrounding areas were classified into seven types based on the Cost733class package, and the weather pattern type 4 (T4), characterized by the strengthened ridge and anticyclone anomaly in northeastern China, was found as the most favorable for the occurrence of extreme summer heat in North China (NCSH). Diagnostic and wave activity flux analyses indicate that the Eurasian teleconnection (EAT) pattern from the atmosphere and the Victoria mode (VM) from the ocean are the top two dominant climate drivers of the T4 weather pattern. The empirical models constructed based on the EAT and the VM can effectively simulate the number of days of the T4 weather pattern and the NCSH, respectively. Our results suggest that, with the help of the seasonal forecast from climate models, the EAT and the VM can be used to predict the number of days of the T4 weather pattern and the NCSH for the coming summer, enabling us to protect human health and reduce its socioeconomic impacts through proactive measures in advance.

Safety and immunogenicity of a modified Omicron-adapted inactivated vaccine in healthy adults: a randomized, double-blind, active-controlled Phase III clinical trial.

Updated vaccine strategies are needed to protect against new SARS-CoV-2 variants with increased immune escape. Here, information on the safety and immunogenicity of an inactivated Omicron-adapted vaccine is presented, as compared with CoronaVac. A randomized, double-blind, active-controlled, phase III clinical trial was conducted to compare a modified Omicron-adapted vaccine (Omicron vaccine) with the authorized prototype vaccine (CoronaVac®) as a booster dose. Healthy adults aged ≥18 years, who have previously received 2 or 3 doses of CoronaVac (2C or 3C cohort) at least 6 months before, were enrolled to get a booster dose of Omicron vaccine or CoronaVac in a ratio of 2:1 (2C/3C+1O/1C). Back-up serums after two initial doses of CoronaVac (2C+0) for adults aged 26-45 years were collected from a previous study. Immunogenicity and safety data at 28 days after vaccination were collected and analyzed. One of the primary objectives was to evaluate the superiority of immunogenicity of Omicron vaccine booster against Omicron BA.1, compared with CoronaVac booster against BA.1. Another objective was to evaluate the non-inferiority of immunogenicity of Omicron vaccine booster against BA.1, compared with two initial doses of CoronaVac against ancestral strain. Between June 1st and July 21st, 2022, a total of 1,500 healthy adults were enrolled. Results show that all pre-specified superiority criteria for BA.1 neutralizing antibody were met. Specifically, within the 3C cohort (3C+1O vs. 3C+1C), the geometric mean titers' (GMT) ratio and 95% confidence interval (CI) was 1.64 (1.42, 1.89), with the lower 95%CI ≥1; a GMT ratio of 1.84 (1.57, 2.16) was observed for 2C+1O versus 3C+1C. For seroconversion rate, the lower 95%CIs of differences between immuno-comparative groups (2/3C+1O vs. 3C+1C) were all above the superiority criterion 0%. However, the non-inferiority criterion of the lower 95%CI of GMT ratio ≥2/3 was unfulfilled for 2C/3C+1O against BA.1 versus 2C+0 against ancestral strain. Safety profiles were similar between groups, with no safety concerns identified. The Omicron-adapted vaccine was well-tolerated and could elicit superior immune responses as compared with CoronaVac against Omicron, while it appeared inferior to CoronaVac against ancestral strain. https://classic.clinicaltrials.gov/ct2/show/NCT05381350?term=NCT05381350&draw=2&rank=1, identifier NCT05381350.