Southern Ocean wind stress in CMIP5 models: Role of wind fluctuations

The Southern Ocean (SO) surface wind stress is a major atmospheric forcing for driving the Antarctic Circumpolar Current and the global overturning circulation. Here the effects of wind fluctuations at different time scales on SO wind stress in 18 models from phase 5 of the Coupled Model Intercomparison Project (CMIP5) are investigated. It is found that including wind fluctuations, especially on time scales associated with synoptic storms, in the stress calculation strongly enhances the mean strength, modulates the seasonal cycle, and significantly amplifies the trends of SO wind stress. In 11 out of the 18 CMIP5 models, the SO wind stress has strengthened significantly over the period of 1960-2005. Among them, the strengthening trend of SO wind stress in one CMIP5 model is due to the increase in the intensity of wind fluctuations, while in all the other 10 models the strengthening trend is due to the increasing strength of the mean westerly wind. These discrepancies in SO wind stress trend in CMIP5 models may explain some of the diverging behaviors in the model-simulated SO circulation. Our results suggest that to reduce the uncertainty in SO responses to wind stress changes in the coupled models, both the mean wind and wind fluctuations need to be better simulated

Simulated impact of Southern Hemisphere westerlies on Antarctic Shelf Bottom Water temperature

The Southern Hemisphere (SH) westerly winds have intensified and shifted poleward since the 1970s and this trend is projected to sustain under future anthropogenic forcing. The influences of intensified SH westerlies on the Antarctic coastal waters are still not clear. The variability of Antarctic Continental Shelf Bottom Water (ASBW) temperature is crucial for ice shelf basal melting and hence ice shelf mass balance in Antarctica. In order to understand the impacts of SH westerlies on the variability of ASBW temperature, atmospheric forcing in 1992 with weak westerlies and in 1998 with strong westerlies are used to drive a high-resolution ocean-sea ice general circulation model, MITgcm-ECCO2. Our simulated results show that under the atmospheric forcing in 1998, the ASBW becomes warmer in most regions around Antarctica except the coastal region between 60°–150°W, than for the case under atmospheric forcing in 1992. The warming of ASBW around Antarctica is due to the intense shoaling and warming of CDW induced by enhanced Ekman pumping as well as strengthened subpolar gyres. The strengthened subpolar gyres favor the transportation of warm water to the coast of Antarctica. The cooling of ASBW along the coast of the western Antarctic Peninsula is caused by stronger coastal currents, which bring colder water downstream from the northwest flank of the Weddell Sea

Mean, variability and trend of Southern Ocean wind stress: Role of wind fluctuations

The Southern Ocean (SO) surface westerly wind stress plays a fundamental role in driving the Antarctic Circumpolar Current and the global meridional overturning circulation. Here we investigate the contributions of atmospheric wind fluctuations to the mean, variability and trend of SO wind stress over the last four decades using NCEP and ERA-Interim reanalysis products. Including wind variability at synoptic frequencies (2-8 days) and higher in the stress calculation is found to increase the strength of the mean SO wind stress by almost 40% in both reanalysis products. The Southern Annular Mode index is found to be a good indicator for the strength of the mean wind and mean wind stress, but not as good an indicator for wind fluctuations, at least for the chosen study period. Large discrepancies between reanalysis products emerge regarding the contributions of wind fluctuations to the strengthening trend of SO wind stress. Between one-third and half of the stress trend in NCEP can be explained by the increase in the intensity of wind fluctuations, while the stress trend in ERA-Interim is due entirely to the increasing strength of the mean westerly wind. This trend discrepancy may have important climatic implications since the sensitivity of SO circulation to wind stress changes depends strongly on how these stress changes are brought about. Given the important role of wind fluctuations in shaping the SO wind stress, studies of the SO response to wind stress changes need to account for changes of wind fluctuations in the past and future

A novel sulfur dioxide probe inhibits high glucose-induced endothelial cell senescence

Sulfur dioxide (SO2) is an important gas signal molecule produced in the cardiovascular system, so it has an important regulatory effect on human umbilical vascular endothelial cells (HUVECs). Studies have shown that high glucose (HG) has become the main cause of endothelial dysfunction and aging. However, the mechanism by which SO2 regulates the senescence of vascular endothelial cells induced by HG has not yet been clarified, so it is necessary to find effective tools to elucidate the effect of SO2 on senescence of HUVECs. In this paper, we identified a novel sulfur dioxide probe (2-(4-(dimethylamino)styryl)-1,1,3-trimethyl-1H-benzo [e]indol-3-ium, DLC) that inhibited the senescence of HUVECs. Our results suggested that DLC facilitated lipid droplets (LDs) translocation to lysosomes and triggered upregulation of LAMP1 protein levels by targeting LDs. Further study elucidated that DLC inhibited HG-induced HUVECs senescence by promoting the decomposition of LDs and protecting the proton channel of V-ATPase on lysosomes. In conclusion, our study revealed the regulatory effect of lipid droplet-targeted sulfur dioxide probes DLC on HG-induced HUVECs senescence. At the same time, it provided the new experimental evidence for elucidating the regulatory mechanism of intracellular gas signaling molecule sulfur dioxide on vascular endothelial fate

Prevalence and factors of COVID-19 vaccine refusal among solid cancer patients in China: an application of the health belief model

IntroductionIt is essential to protect cancer patients from contracting COVID-19 through vaccination. A majority of cancer patients are recommended by international health authorities to take up the vaccines. COVID-19 vaccine refusal among cancer patients during the pandemic period is under-researched. This study investigated factors of vaccine refusal based on the Health Belief Model (HBM).MethodsA cross-sectional study was conducted among female breast cancer patients, male/female thyroid cancer patients, and gynecological cancer patients in Shantou, China from April to August 2022 (n = 1,115). Multinomial logistic regression analysis adjusted for socio-demographics was conducted to test factors of COVID-19. Adjusted odds ratios of the two models comparing vaccine refusal vs. “vaccine non-refusal” and vaccine refusal vs. ever-vaccination were derived and presented.ResultsOf all the participants, the prevalence of vaccine refusal, “vaccine non-refusal,” and ever-vaccination was 25.9, 22.2, and 51.8%, respectively. In both multinomial logistic regression models, significant factors of vaccine refusal included socio-demographics (age, education level, employment status, monthly household income, cancer type, duration since cancer diagnosis, current treatment status) and some vaccine-related HBM (perceived benefits, perceived barriers, cue to action, and self-efficacy). Perceived severity of COVID-19 was significant only in the vaccine refusal vs. ever-vaccination model. In neither model, perceived susceptibility to contract COVID-19 was statistically significant.ConclusionAbout ¼ of the participants expressed vaccine refusal. Interventions are warranted. Future longitudinal studies are needed to verify this study’s findings. Pilot interventions should also be launched to test effectiveness of interventions modifying the significant HBM factors found in this study

A Study on the Mechanism of Urea-assisted Steam Flooding in Heavy Oil Reservoirs

The Biqian-10 block, located in Henan Oilfield of Sinopic, contains many thin and interbedded reservoirs, which have been operated by cyclic steam stimulation for 20 years or more. Therefore, it is a challenge to implement the conventional steam flooding. In order to improve the recovery of steam flooding, urea was used to assist steam flooding. Urea can decompose into CO2 and NH3, which are beneficial to enhance oil recovery (EOR). For the sake of exactly quantifying the mechanism of urea assisted steam flooding (UASF), the UASF model was built according to the experimental results. The simulation results show that CO2 is the key point for EOR, and its pressurization function is more effective than the decrease in oil viscosity by dissolving CO2. The emulsification of crude oil for NH3 is weak in interfacial tension tests; thus the effect of emulsification can be ignored in the simulation. The UASF can improve the recovery by about 17.4%, which is 6.8% higher than steam flooding.</span

RESEARCH ON CO2 FLOODING FOR IMPROVED OIL RECOVERY IN WATER FLOODING ABANDONED RESERVOIRS

CO2 injection is an effective technique for improved oil recovery in light oil reservoirs, especially for water flooding abandoned reservoirs. In this study, the lower part of Es1 reservoirs in Pucheng oilfield was introduced as the target reservoir. By studying the minimum miscible pressure in CO2 flooding, the reservoir could achieve miscible flooding. Long core displacement experiments proved that water alternating CO2 flooding could significantly improve the recovery. For the reservoir characteristics, anti-corrosion technology in the process of injection was researched, and the H-20 inhibitor was screened. A channeling blocking agent in combination with the delayed expansion of gel particles and cross-linked copolymer was used to control the gas fluidity. The Pu 1-1 well groups were optimized to conduct a field trial. The cumulative injected liquid CO2 was 19219.95 ton, 0.248 PV and the cumulative increasing oil was 4520.9 t. The predicted recovery will increase by 8.3%. The successful implementation of the project can provide technical attempt for completion of energy to succeed and energy-saving emission reduction targets.</span

Mean and seasonal circulation of the eastern Chukchi Sea from moored timeseries in 2013-2014

Author Posting. © American Geophysical Union, 2021. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Oceans 126(5), (2021): e2020JC016863, https://doi.org/10.1029/2020JC016863.From late-summer 2013 to late-summer 2014, a total of 20 moorings were maintained on the eastern Chukchi Sea shelf as part of five independent field programs. This provided the opportunity to analyze an extensive set of timeseries to obtain a broad view of the mean and seasonally varying hydrography and circulation over the course of the year. Year-long mean bottom temperatures reflected the presence of the strong coastal circulation pathway, while mean bottom salinities were influenced by polynya/lead activity along the coast. The timing of the warm water appearance in spring/summer is linked to advection along the various flow pathways. The timing of the cold water appearance in fall/winter was not reflective of advection nor related to the time of freeze-up. Near the latitude of Barrow Canyon, the cold water was accompanied by freshening. A one-dimensional mixed-layer model demonstrates that wind mixing, due to synoptic storms, overturns the water column resulting in the appearance of the cold water. The loitering pack ice in the region, together with warm southerly winds, melted ice and provided an intermittent source of fresh water that was mixed to depth according to the model. Farther north, the ambient stratification prohibits wind-driven overturning, hence the cold water arrives from the south. The circulation during the warm and cold months of the year is different in both strength and pattern. Our study highlights the multitude of factors involved in setting the seasonal cycle of hydrography and circulation on the Chukchi shelf.The authors are extremely grateful to all of these individuals, and to the funding agencies that supported the respective field programs: The Bureau of Ocean Energy Management; The National Oceanic and Atmospheric Administration; The National Science Foundation; and The Japanese Agency for Marine-Earth Science and Technology. Support for this analysis was provided by the following grants: National Oceanic and Atmospheric Administration grant NA14OAR4320158; National Science Foundation grants PLR-1504333, OPP-1733564, PLR-1758565; North Pacific Research Board grants A91-99a and A91-00a; Chinese Arctic and Antarctic grant CXPT2020009; Natural Sciences and Engineering Research Council of Canada

Phi meson production in Au+Au and p+p collisions at sqrt (s)=200 GeV

We report the STAR measurement of Phi meson production in Au+Au and p+p collisions at sqrt (s)=200 GeV. Using the event mixing technique, the Phi spectra and yields are obtained at mid-rapidity for five centrality bins in Au+Au collisions and for non-singly-diffractive p+p collisions. It is found that the Phi transverse momentum distributions from Au+Au collisions are better fitted with a single-exponential while the p+p spectrum is better described by a double-exponential distribution. The measured nuclear modification factors indicate that Phi production in central Au+Au collisions is suppressed relative to peripheral collisions when scaled by the number of binary collisions. The systematics of versus centrality and the constant Phi/K- ratio versus beam species, centrality, and collision energy rule out kaon coalescence as the dominant mechanism for Phi production.Comment: 6 pages, 3 figures, submitted to Phys. Rev. Let