A consistent finding of high-obliquity simulations is that they are warmer than their low-obliquity counterparts when the climate is cold. Ice-albedo feedback has been suggested as a possible ...mechanism. In this study, we find that a warmer climate under high obliquity holds with varying insolations, including almost ice-free conditions. We try to understand the mechanisms through a series of feedback suppression experiments. When the ice-albedo feedback is turned off, the temperature contrast between high and low obliquity remains significant, but it vanishes when the cloud radiation effects or the seasonal variation is turned off. This suggests that a warmer climate on high-obliquity planets does not rely completely on the existence of ice, and therefore holds at high insolation. In that regime, the surface temperature, and hence the cloud formation, lags behind the substellar point, leading to inefficient sunlight reflection and a warmer climate.
This paper aims to explore the correlation and influencing factors between cultural identity and historical development using the historiometric method. Meanwhile, a genetic algorithm is used to ...collect historical data and quantitative indicators of cultural identity, which is then combined to construct a mathematical model of historical development and cultural identity. The optimization of the model involves using genetic algorithms to find the best match and optimal solution. The historical measures score up to 9.5 due to the significant impact of cultural identity on historical development. This study provides new methods and perspectives for a deeper understanding of the interaction between cultural identity and historical development and is of great significance in promoting the development of historical research and cultural identity research.
Sudden stratospheric warming (SSW) events influence the Arctic Oscillation and midlatitude extreme weather. Observations show SSW events to be correlated with certain phases of the Madden–Julian ...oscillation (MJO), but the effect of the MJO on SSW frequency is unknown, and the teleconnection mechanism, its planetary wave propagation path, and time scale are still not completely understood. The Arctic stratosphere response to increased MJO forcing expected in a warmer climate using two models is studied: the comprehensive Whole Atmosphere Community Climate Model and an idealized dry dynamical core with and without MJO-like forcing. It is shown that the frequency of SSW events increases significantly in response to stronger MJO forcing, also affecting the averaged polar cap temperature. Two teleconnection mechanisms are identified: a direct propagation of MJO-forced transient waves to the Arctic stratosphere and a nonlinear enhancement of stationary waves by the MJO-forced transient waves. The MJO-forced waves propagate poleward in the lower stratosphere and upper troposphere and then upward. The cleaner results of the idealized model allow identifying the propagating signal and suggest a horizontal propagation time scale of 10–20 days, followed by additional time for upward propagation within the Arctic stratosphere, although there are significant uncertainties involved. Given that the MJO is predicted to be stronger in a warmer climate, these results suggest that SSW events may become more frequent, with possible implications on tropospheric high-latitude weather. However, the effect of an actual warming scenario on SSW frequency involves additional effects besides a strengthening of the MJO, requiring further investigation.
Abstract
As one of the most detectable types of terrestrial planets, lava worlds are highly prioritized targets for exoplanet atmosphere characterization since their atmospheres may reveal what they ...are made of and how. Our work examines the possibility of true polar wander (TPW) occurring on these ultrahot tidally locked planets, powered by mass redistribution from atmospheric flow between the hot permanent dayside and the cold permanent nightside. We find that lava planets within a certain mass and temperature range may undergo TPW, and this likelihood increases with star mass. As a result of TPW, the magma ocean and atmospheric compositions may be less evolved (refractory-enriched) than previously thought and may be validated by exoplanet demographic surveys.
Abstract
On icy worlds, the ice shell and subsurface ocean form a coupled system—heat and salinity flux from the ice shell induced by the ice-thickness gradient drives circulation in the ocean, and ...in turn, the heat transport by ocean circulation shapes the ice shell. Therefore, understanding the dependence of the efficiency of ocean heat transport (OHT) on orbital parameters may allow us to predict the ice-shell geometry before direct observation is possible, providing useful information for mission design. Inspired by previous works on baroclinic eddies, I first derive scaling laws for the OHT on icy moons, driven by ice topography, and then verify them against high-resolution 3D numerical simulations. Using the scaling laws, I am then able to make predictions for the equilibrium ice-thickness variation knowing that the ice shell should be close to heat balance. The ice shell on small icy moons (e.g., Enceladus) may develop strong thickness variations between the equator and pole driven by the polar-amplified tidal dissipation in the ice; in contrast, the ice shell on large icy moons (e.g., Europa, Ganymede, Callisto, etc.) tends to be flat due to the smoothing effects of the efficient OHT. These predictions are manifested by the different ice-evolution pathways simulated for Enceladus and Europa, considering the ice freezing/melting induced by ice dissipation, conductive heat loss, and OHT as well as the mass redistribution by ice flow.
ABSTRACT
It has been long puzzling whether the ice thickness variations observed on Enceladus can be sustained solely by a polar-amplified bottom heating. The key to this question is to understand ...how the upward heat transport by convective plumes would be interfered by the temperature and salinity variations beneath the ice due to the ice thickness variations, which, however, has yet to be explored. Here, we find that the horizontal temperature variation induced by the ice topography can easily be orders of magnitude greater than the vertical temperature variation induced by bottom heating using scaling analysis. Due to the dominance of horizontal temperature gradient, convective plumes are completely shut off by a stratified layer under the thin ice formed out of baroclinic adjustment, largely slowing down the vertical tracer transport. The stratified layer will also deflect almost all of the core-generated heating towards the regions with thicker ice shell, destroying the ice thickness gradient. These results allow us to put an upper bound on the core-generated heating on Enceladus, which is crucial for the estimate of habitability. Scaling laws for the bottom heat flux to penetrate the stratification are derived and examined. This scaling can be used to constrain the maximum ice thickness variations induced by heterogeneous bottom heating on icy satellites in general, which can be used to differentiate icy satellites that generate the majority of heat in the ice shell from those that generate the majority of heat in the silicate core.
Over the last decade, mounting evidence has revealed the key roles of gut microbiota in modulating the efficacy and toxicity of anticancer drugs, via mechanisms such as immunomodulation and microbial ...enzymatic degradation. As such, human microbiota presents as an exciting prospect for developing biomarkers for predicting treatment outcomes and interventional approaches for improving therapeutic effects. In this review, we analyze the current knowledge of the interplays among gut microorganisms, host responses and anticancer therapies (including cytotoxic chemotherapy and targeted therapy), with an emphasis on the immunomodulation function of microbiota which facilitates the efficacy of immune checkpoint inhibitors. Moreover, we propose several microbiota-modulating strategies including fecal microbiota transplantation and probiotics, which can be pursued to optimize the use and development of anticancer treatments. We anticipate that future clinical and preclinical studies will highlight the significance of human microbiome as a promising target towards precision medicine in cancer therapies.
National Key Research and Development Program of China (2020YFA0907800), Shenzhen Science and Technology Innovation Program (KQTD20200820145822023) and National Natural Science Foundation of China (31900056 and 32000096).
We investigate how obliquity affects stratospheric humidity using a 3D general circulation model and find the stratosphere under high obliquity could be over 3 orders of magnitude moister than under ...the low-obliquity equivalent, even with the same global annual mean surface temperature. Three complexities that only exist under high obliquity are found to be causally relevant. (1) Seasonal variation under high obliquity causes extremely high surface temperatures to occur during polar days, moistening the polar air that may eventually enter the stratosphere. (2) Unlike the low-obliquity scenario where the cold trap efficiently freezes out water vapor, the high-obliquity stratosphere gets most of its moisture input from high latitudes, and thus largely bypasses the cold trap. (3) A high-obliquity climate tends to be warmer than its low-obliquity equivalent, thus moistening the atmosphere as a whole. We found each of the above factors could significantly increase stratospheric humidity. These results indicate that, for an earth-like exoplanet, it is more likely to detect water from surface evaporation if the planet is under high obliquity. The water escape could cause a high-obliquity planet to loss habitability before the runaway greenhouse takes place.
Anti-PD-1 immunotherapy has saved numerous lives of cancer patients; however, it only exerts efficacy in 10-15% of patients with colorectal cancer. Fecal microbiota transplantation (FMT) is a ...potential approach to improving the efficacy of anti-PD-1 therapy, whereas the detailed mechanisms and the applicability of this combination therapy remain unclear. In this study, we evaluated the synergistic effect of FMT with anti-PD-1 in curing colorectal tumor-bearing mice using a multi-omics approach. Mice treated with the combination therapy showed superior survival rate and tumor control, compared to the mice received anti-PD-1 therapy or FMT alone. Metagenomic analysis showed that composition of gut microbiota in tumor-bearing mice treated with anti-PD-1 therapy was remarkably altered through receiving FMT. Particularly,
Bacteroides
genus, including FMT-increased
B. thetaiotaomicron
,
B. fragilis
, and FMT-decreased
B. ovatus
might contribute to the enhanced efficacy of anti-PD-1 therapy. Furthermore, metabolomic analysis upon mouse plasma revealed several potential metabolites that upregulated after FMT, including punicic acid and aspirin, might promote the response to anti-PD-1 therapy
via
their immunomodulatory functions. This work broadens our understanding of the mechanism by which FMT improves the efficacy of anti-PD-1 therapy, which may contribute to the development of novel microbiota-based anti-cancer therapies.
Enhancing human papillomavirus (HPV) vaccine uptake rates to protect women's health is an important public health issue worldwide. China has taken a series of measures in recent years to promote HPV ...vaccination among school-aged girls, but the vaccine uptake rate remains low. Investigating the factors influencing vaccination-related decision-making of adolescent girls' parents is key to solving the problem. This study aimed to examine the influence of sociocultural-psychological predictors, including exposure to HPV-related stories (positive/negative), affective reactions (pride/regret), injunctive norms on the Internet and perceived moral obligation, on parents' HPV vaccination-related decision-making for girls aged 13-15 years in mainland China.
A cross-sectional online survey using quota sampling was conducted in February 2022. Four hundred and five valid and qualified questionnaires were obtained. Partial least squares structural equation modeling was performed by SmartPLS 3 (i) to evaluate the reliability and validity of the measurement models of 11 constructs, and (ii) to test the effect relationships of the sociocultural-psychological predictors on parents' intention to vaccinate their daughters.
The study findings showed that parental decision-making regarding HPV vaccination was influenced by sociocultural and psychological factors. At the level of individual psychological factors, exposure to positive stories was significantly associated with perceived vaccine effectiveness (β = 0.331,
= 8.448,
< 0.001), which strongly predicted the attitude toward vaccination (β = 0.521,
= 8.133,
< 0.001); anticipated pride had more positive influence on vaccination-related decision-making (β = 0.156,
= 2.176,
< 0.05) than anticipated regret. In terms of social influence, injunctive norms on the Internet had a significantly positive influence on vaccination intention (β = 0.127,
= 2.382,
< 0.05), similar to descriptive norms (β = 0.135,
= 3.358,
< 0.01). Perceived moral obligation at the cultural level was the strongest predictor of parental decision-making regarding HPV vaccination (β = 0.193,
= 2.139,
< 0.05).
This study is the first in mainland China to systematically examine the sociocultural-psychological predictors of parents' decision-making to vaccinate their 13-15-year-old daughters against HPV. A new extended TPB model with a sociocultural-psychological approach was developed. This model can support the investigation of factors affecting HPV vaccine uptake rates in the mainland Chinese population and similar populations and help to understand the differences in vaccination-related decision-making between Eastern and Western cultures. Furthermore, the study provided some suggestions for HPV vaccination communication campaigns targeting adolescent girls' parents.
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