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The Pacific Meridional Modes (PMMs) are the leading ocean-atmosphere coupled modes in the subtropical northeastern (NPMM) and southeastern (SPMM) Pacific, respectively, and have been suggested to be key precursors to equatorial Pacific variability. Previous studies pointed out that both PMMs-related sea surface temperature (SST) anomalies are primarily driven by net surface heat flux variations during their equatorward evolution. However, whether ocean heat advective processes would play a role during the evolution remains unclear. To address this issue, we perform an ocean mixed-layer heat budget analysis based on observations and three ocean reanalysis datasets, and then reveal the effect of ocean advections on the evolution by comparing a fully coupled dynamic ocean model (DOM) to a slab ocean model (SOM). Our results suggest that for the NPMM evolution, ocean advections—primarily by anomalous meridional Ekman heat advections driven by mean and anomalous zonal wind stresses—play a damping role in the south of the NPMM, resulting in the NPMM shifts poleward but still freely propagates westward from preceding boreal winter to the following summer. This finding challenges the traditional view that the NPMM propagates equatorward through the wind-evaporation-SST feedback. For the SPMM evolution, ocean advections play a damping role in the center of the SPMM from boreal spring to summer, as well as an intensification role in the southwest Pacific during summer. However, the effect of the intensification on the SPMM evolution is hard to be revealed due to the strong simulation bias of the SPMM evolution in the DOM.

Coronavirus disease 2019 (COVID-19) is a rapidly spreading disease that has caused an extensive burden to the world. Consequently, a large number of clinical trials have examined the efficacy of traditional Chinese medicine (TCM) for treating and preventing COVID-19, with coinciding proliferation of reviews summarizing these studies.This study aimed to evaluate the methodological quality and evidence quality of systematic reviews and meta-analyses on the efficacy of TCM.Seven electronic databases, including PubMed, Cochrane Library, Web of Science, China National Knowledge Infrastructure, Chongqing VIP, Wanfang Data and SinoMed, were searched for systematic reviews and meta-analyses in October 2021. Search terms such as "Chinese medicine," "Lianhua Qingwen" and "COVID-19" were used.Systematic reviews and meta-analyses of randomized controlled trials that evaluated the efficacy of TCM treatment of COVID-19 were included.A Measurement Tool to Assess Systematic Reviews Version 2.0 (AMSTAR 2) was used to evaluate the methodological quality. The quality of evidence was graded using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. Data extraction and analysis were performed by two reviewers independently.There were 17 meta-analyses included in our overview. The intervention group was defined as TCM combined with Western medicine, while the control group was Western medicine alone. The methodological quality of all the included studies was moderate to poor. A total of 89 outcome indicators were evaluated, of which, 8 were rated as moderate quality, 39 as low quality, and 41 as very low quality. Only one outcome measure was graded as being of high quality. The moderate quality of evidence indicated that, for the treatment of COVID-19, the clinical efficacy of TCM in combination with Western medicine was better, in terms of lung recovery, rate of conversion to severe/critical cases, symptom scores, duration of symptoms, mortality, and length of hospital stay.Evidence from the included studies shows that, compared with conventional Western medical therapy alone, the addition of TCM to COVID-19 treatment may improve clinical outcomes. Overall, the quality of evidence of TCM for COVID-19 was moderate to poor. Meta-analyses of the use of TCM in the treatment of COVID-19 can be used for clinical decision making by accounting for the experiences of clinical experts, medical policies, and other factors.

Sea surface temperature (SST) variability in the North Pacific (NP) has broad impacts on climate, ecology, and fishing, but its decadal prediction remains challenging. Some studies have highlighted the importance of tropical Pacific forcing on NP SST variability, while others suggested a non-negligible role of North Atlantic forcing. The contribution of each region to NP SST decadal prediction needs to be carefully evaluated. Here, we apply linear inverse models (LIMs) to assess decadal prediction skill of observed NP SST (based on predictions averaged over 2–5 and 6–9 years in advance). By using model experiments that restore to observed SST variability, we quantify tropical Pacific and North Atlantic forcing, and find that the latter exhibits stronger contribution than the former to NP SST decadal prediction. Specifically, by removing the North Atlantic forcing (tropical Pacific forcing), the area ratio of the NP region with significant prediction skill reduces from 49% to 29% (43%) for years 2–5 and from 48% to 26% (44%) for years 6–9. Further analyses reveal the possible reason: NP SST decadal prediction is strongly modulated by two leading non-orthogonal patterns of the LIMs with long decay time (although higher-order patterns also play a role for years 2–5); the North Atlantic forcing largely and robustly contributes to the long decay time, while the tropical Pacific forcing plays a secondary role. Our study calls for more efforts on improving the simulation of the Atlantic trans-basin effect for better predicting NP climate.

Investigating Pacific Meridional Modes (PMM) without the influence of tropical Pacific variability is technically difficult if based on observations or fully coupled model simulations due to their overlapping spatial structures. To confront this issue, the present study investigates both North (NPMM) and South PMM (SPMM) in terms of their associated atmospheric forcing and response processes based on a mechanically decoupled climate model simulation. In this experiment, the climatological wind stress is prescribed over the tropical Pacific, which effectively removes dynamically coupled tropical Pacific variability (e.g., the El Niño-Southern Oscillation). Interannual NPMM in this experiment is forced not only by the North Pacific Oscillation, but also by a North Pacific tripole (NPT) pattern of atmospheric internal variability, which primarily forces decadal NPMM variability. Interannual and decadal variability of the SPMM is partly forced by the South Pacific Oscillation. In turn, both interannual and decadal NPMM variability can excite atmospheric teleconnections over the Northern Hemisphere extratropics by influencing the meridional displacement of the climatological intertropical convergence zone throughout the whole year. Similarly, both interannual and decadal SPMM variability can also excite atmospheric teleconnections over the Southern Hemisphere extratropics by extending/shrinking the climatological South Pacific convergence zone in all seasons. Our results highlight a new poleward pathway by which both the NPMM and SPMM feed back to the extratropical climate, in addition to the equatorward influence on tropical Pacific variability.

Moisture transport from the Atlantic to Pacific is important for basin-scale freshwater budget and the formation of meridional ocean circulation. Although the climatological tropical Atlantic-to-Pacific moisture transport (TAPMORT) has been well investigated, few studies have focused on its variability. Here we investigate the interannual variability of TAPMORT based on the atmospheric reanalysis data sets. The TAPMORT interannual variability is dominated by the variations of trans-basin winds across Central America, and peaks in late boreal summer and late boreal winter. 1) In late summer, a developing El Niño and a mature Atlantic Niña set up an interbasin sea-surface temperature (SST) gradient that strengthens the low-level jet across Central America and therefore TAPMORT (with weakened TAPMORT for opposite signed events). This process typically occurs from July to September, with a peak in August. 2) In late winter, the strengthened southern North American center of the Pacific-North American-like pattern intensifies the TAPMORT variations. Although atmospheric interannual variability dominates these variations, extreme El Niño events are also important for the teleconnections. This process shows a single peak in February, in contrast to the persistent peak in late summer. We further demonstrate that the persistent TAPMORT variability in late summer dominates the moisture divergence over the northwestern tropical Atlantic and modulates freshwater flux there. Thus, our study improves the understanding of how TAPMORT interannual variability and the related interbasin SST gradient regulate the northwestern tropical Atlantic freshwater budget and the related salinity variability.

Internally generated decadal variability influences global mean surface temperature (GMST), inducing acceleration and slowdown of the warming rate under anthropogenic radiative forcing1–4. While tropical eastern Pacific variability is important for annual-mean GMST2,5–8, the cold ocean–warm land (COWL) pattern9,10 also contributes to continental temperature variability11–13 in the boreal cold season. Although the two contributors are physically independent10,12, here we show that, after the mid-1980s, their decadal components vary in phase by chance to strengthen internal GMST trends, contributing to the early 2000s slowdown and early 2010s acceleration. The synchronized tropical Pacific and COWL variability explains the striking seasonality of the recent slowdown and acceleration during which the GMST trend in the boreal cold season is markedly negative and positive, respectively. Climate models cannot simulate the exact timing of the tropical Pacific and COWL correlations because they are physically independent, random-phased modes of internal variability. Natural decadal variability has a role in global mean surface temperature trends. Observational data and modelling show that since the mid-1980s, the tropical eastern Pacific variability and the cold ocean–warm land pattern have covaried to enhance acceleration and deceleration in warming trends.

Equatorial Pacific decadal variability (EPDV) modulates global climate. Although EPDV is suggested to be generated by both air-sea thermodynamically coupled slab ocean models (SOM) and fully couple...

The subtropical northeastern Pacific (SNEP) acts as a bridge conveying information between the North and tropical Pacific. While most studies have investigated the SNEP sea surface temperature (SST...

The Pacific decadal oscillation (PDO) is the leading mode of sea surface temperature (SST) variability over the North Pacific (north of 20°N). Its South Pacific counterpart (south of 20°S) is the South Pacific decadal oscillation (SPDO). The effects of tropical eastern Pacific (TEP) SST forcing and internal atmospheric variability are investigated for both the PDO and SPDO using a 10-member ensemble tropical Pacific pacemaker experiment. Each member is forced by the historical radiative forcing and observed SST anomalies in the TEP region. Outside the TEP region, the ocean and atmosphere are fully coupled and freely evolve. The TEP-forced PDO (54% variance) and SPDO (46% variance) are correlated in time and exhibit a symmetric structure about the equator, driven by the Pacific–North American (PNA) and Pacific–South American teleconnections, respectively. The internal PDO resembles the TEP-forced component but is related to internal Aleutian low (AL) variability associated with the Northern Hemisphere annular mode and PNA pattern. The internal variability is locally enhanced by barotropic energy conversion in the westerly jet exit region around the Aleutians. By contrast, barotropic energy conversion is weak associated with the internal SPDO, resulting in weak geographical preference of sea level pressure variability. Therefore, the internal SPDO differs from the TEP-forced component, featuring SST anomalies along ~60°S in association with the Southern Hemisphere annular mode. The limitations on isolating the internal component from observations are discussed. Specifically, internal PDO variability appears to contribute significantly to the North Pacific regime shift in the 1940s.

A transbasin mode (TBM) is identified as the leading mode of interannual surface wind variability over the Intra-Americas Seas across Central America based on empirical orthogonal function analysis. The TBM is associated with variability in Central American gap winds, most closely with the Papagayo jet but with considerable signals over the Gulfs of Tehuantepec and Panama. Although El Niño–Southern Oscillation (ENSO) is the main large-scale forcing, the TBM features a distinct seasonality due to sea level pressure (SLP) adjustments across the Pacific and Atlantic. During July–September, ENSO causes meridional SLP gradient anomalies across Central America, intensifying anomalous geostrophic winds funneling through Papagayo to form the TBM. During wintertime, ENSO peaks but imparts little anomalous SLP gradient across Central America with a weak projection on the TBM because of the competing effects of the Pacific–North American teleconnection and tropospheric Kelvin waves. Besides ENSO, tropical Atlantic sea surface temperature anomalies make a weak contribution to the TBM in boreal summer by strengthening the cross-basin gradient. ENSO and the Atlantic forcing constitute a cross-basin seesaw pattern in SLP, manifested as an anomalous Walker circulation across the tropical Americas. The TBM appears to be part of the low-level branch of the anomalous Walker circulation, which modulates Central American wind jets by orographic effect. This study highlights the seasonality of gap wind variability, and calls for further research into its influence on regional climate.

Distribution characteristics, chemical constituents, and sources of particulate matter were measured using a scanning mobility particle sizer and single particle aerosol mass spectrometer during pollution monitoring that occurred between December 5

To study the chemical composition and pollution sources of the fine particulate matter during the four seasons in Nanning, single particle aerosol mass spectrometry was performed to characterize the fine particulate matter in Nanning during the four seasons. The correlation (

Two hundred eighteen PM

It is well known that radioactive rays may cause damage to the human body. Progress in modern medicine has led to an increased risk of therapeutic and diagnostic radiation exposure of patients. Although clear evidence of a radiation dose-dependent risk of chronic myeloid leukaemia, particularly for patients exposed to radiation at a young age, has been established, it is not known whether radiation exposure during diagnostic imaging also increases the risk of cancer. The present study reports the case of a patient who underwent several diagnostic imaging tests (including repeated chest radiography and computed tomography) for recurrent pneumothorax. At around one year subsequent to these tests, the patient was diagnosed with chronic myeloid leukaemia. The patient exhibited an increase in white blood cell count over time, and a bone marrow smear test showed a myeloid/erythroid ratio of 13.9:1. In addition, the qualitative breakpoint cluster region (BCR)/Abelson (ABL) gene test revealed positive results for BCR/ABL fusion (p210). Based on the data reported in the current case, research aimed at elucidating the potential risks associated with diagnostic radiation is urgently required. It is crucial that medical professionals consider the potential harmful side effects of diagnostic radiation when ordering radiation-based diagnostic imaging examinations.

Pulmonary fibrosis is characterized by the destruction of lung tissue architecture and the formation of fibrous foci, currently has no satisfactory treatment. Emodin is a component of Chinese herb that has been reported to be medicament on pancreatic fibrosis and liver fibrosis. However, its role in pulmonary fibrosis has not been established yet. In the present study, we investigated the hypothesis that Emodin plays an inhibitory role in TGF-β1 induced epithelial-mesenchymal transition (EMT) of alveolar epithelial cell, and Emodin exerts its effect through the Notch signaling pathway. Emodin inhibits the proliferation of Rat alveolar type II epithelial cells RLE-6TN in a concentration-dependent manner; reduces the expression of Collagen I, α-SMA and Vimentin, promotes the expression of E-cadherin. Moreover, Emodin could regulate the expression patterns of the Notch signaling pathway-related factors and reduce the Notch-1 nucleus translocation. Knockdown of Notch-1 enhances the inhibitory effect of Emodin on TGF-β1-induced EMT in RLE-6TN cells. In conclusion, the data of the present study suggests that Emodin suppresses TGF-β1-induced EMT in alveolar epithelial cells through Notch signaling pathway and shows the potential to be effective in the treatment of pulmonary fibrosis.

Single Particle Aerosol Mass Spectrometry (SPAMS) was performed to characterize the PM2.5 in Nanning from 15 to 24 February 2015. The correlation (R2) between the PM2.5 number concentration and the mass concentration of PM2.5 obtained using SPAMS was 0.76. The particle number concentration could reflect the atmospheric pollution situation to some degree. The Art-2a classification method was used to classify the chemical composition of PM2.5. The results showed that the principal chemical constituents were elemental carbon, organic elements carbon hybrid particles, organic carbon, rich potassium particles, mineral substance, rich sodium particles, second inorganic particles, levoglucosan and other heavy metals. Among them, the composition of elemental carbon was the highest, followed by organic carbon and rich potassium particles. The particle size of 80% of PM2.5 was mainly concentrated in the range of 0.2 microm to 1.0 microm with a peak value occurring at 0. 62 microm. The particle size distribution characteristics of different chemical components were similar. The number concentration of the chemical components in PM2.5 had the same variation tread with the mass concentration of PM2.5 over time. To a certain extent, the change in chemical composition could reflect the instantaneous pollution source.

To explore the effect of polydatin on the growth of TGF-β₁induced humanalveolar epithelium A549 cells and the mechanism of polydatin for inhibiting the process of epithelial-mesenchymal transition (EMT).A549 cells in vitro cultured were randomly divided into five groups, i.e., the blank group, the control group, the low dose polydatin group, the middle dose polydatin group, the high dose polydatin group. Common culture fluid was added in A549 cells of the blank group. Five ng/mLTGF-β₁contained culture fluid was added in A549 cells of the control group. 50, 100, and 150 μmol/mL of polydatin plus 5 ng/mL TGF-β₁contained culture fluid was added in A549 cells of low, middle, and high dosepolydatin groups, respectively. Morphological changes were observed and recorded at different time points. The optimal concentration of polydatin was determined by MTT method. Protein and mRNA expressions of E-cad epithelial cell marker) and Vimentin (mesenchymal cell marker) were detected by Western blot and Real-time PCR.Under inverted phase contrast microscope, A549 cells turned from previous pebble shape to fusiform shape after intervened by polydatin and TGF-β1. The intercellular space was enlargedand the intercellular connection became loose. These phenomena were more obviously seen in the control group. A549 cells were more satiated in low, middle, and high dose polydatin groups than in the control group. The EMT inhibition was most obviously seen in the middle dose polydatin group at 48 h. Protein and mRNA expressions of E-cad showed an overall descending tendency after intervened by polydatin and TGF-β1 (P0.05). But compared with the control group, protein and mRNA expressions of E-cad were down-regulated in a lesser amplitude in each intervened group. Besides, the tendency was more obviously seen at 48 h than at 24 h. Protein and mRNA expressions of Vimentin showed an overall up-regulating tendency. But compared with the control group, protein and mRNA expressions of Vimentin were down-regulated in a lesser amplitude in each intervened group. Besides, the tendency was more obviously seen at 48 h than at 24 h (P0.05). CONCLUSIONS Polydatin could inhibit TGF-β1 induced EMT process of A549 cells time- and dose-dependently. It also played roles in inhibiting pulmonary fibrosis.

To study the effect of Flos Daturae alkaloids (FDA) on TGF-beta1-1uuuu;U epithelial-mesenchymal transition (EMT) of human pulmonary adenocarcinoma A549 cells.A549 cells in vitro cultured were randomly divided into 5 groups, i.e., the blank control group, the TGF-beta1 group, the low dose FDA group, the medium dose FDA group, and the high dose FDA group. The morphologies of A549 cells were observed. Expressions of cytokeratin (CK)-19 and alpha-smooth muscle actin (alpha-SMA) were detected by Western blot and real-time PCR at 24, 48, and 72 h, respectively.A549 cells in the TGF-beta1, group turned from cobblestone to spindle shape gradually. Those in low, medium and high dose FDA groups showed similar shapes to those of the TGF-beta1 group. There was no statistical difference in the morphology of A549 cells among the 3 dose FDA groups (P0.05). Western blot showed that, when compared with the blank control group, the expression of CK-19 was down-regulated, but the expression of alpha-SMA was up-regulated in the TGF-beta1 group (P0.01). Compared with the TGF-beta1, group, the expression of CK-19 was up-regulated, but the expression of alpha-SMA was suppressed in low, medium and high dose FDA groups (P0.01). The CK-19 expression obviously increased, but the alpha-SMA expression was suppressed in high dose FDA group at 72 h (P0.01). Real-time PCR results showed, as compared with the TGF-beta1 group, the mRNA expression of CK-19 was increased, but the mRNA expression of alpha-SMA was reduced in low, medium and high dose FDA groups (P0.01).FDA had no effect on EMT morphological changes of TGF-beta1 induced A549 cells. FDA could reverse characteristic markers of A549 cells during EMT to some extent, such as expressions of CK-19 and alpha-SMA. The expression of CK-19 (as the epithelium marker) increased and the expression of alpha-SMA (as the mesenchymal marker) was reduced. Besides, they were most obviously seen in the high dose FDA group at 72 h in a dose- and time-dependent manner.

To explore the effect of qidong huoxue decoction (QHD) on inflammatory factors and Toll-like receptor (TLR4) mRNA expressions in acute lung injury (ALI) rats.Totally 50 healthy male SD rats were randomly divided into the blank control group, the lipopolysaccharide (LPS) model group, low, middle, high dose QHD groups according to body weight, 10 rats in each group. Rats in low, middle, high dose QHD groups were intragastrically administered with QHD at 4, 8, and 16 mL/kg 24, 12 h before modeling and 12 h after modeling, respectively. Normal saline was intragastrically administered to rats in the blank control group and the LPS model group. An ALI rat model was established using intratracheal instillation of LPS. Rats were killed after 24-h modeling. Then the bronchoalveolar lavage fluid was prepared. Contents of TNF-α, IL-1β, and L-10 were detected using ELISA. TLR4 mRNA expressions were determined byreal time PCR.Compared with the blank control group, contents of TNF-α, IL-1β , and IL-10 increased (P0. 01), TLR4 mRNA expressions also increased in the LPS model group (all P0. 01). Compared with the LPS model group, contents of TNF-α and IL-1β decreased (P0. 05, P0. 01), IL-10 levels increased (P0. 01) , TLR4 mRNA expressions were also reduced (P0. 01), in high and middle dose QHD groups. Compared with the high dose QHD group, con- tents of TNF-α and IL-1β increased in middle and low dose QHD groups (P0. 05); IL-10 levels decreased (P0. 05) in the low dose QHD group(P0. 05), TLR4 mRNA expressions also increased in the low dose QHD group (P0. 05). Compared with the middle dose QHD group, IL-10 levels was reduced, but TLR4 mRNA expressions increased in the low dose QHD group (P0. 05).QHD had the protective effect on LPS induced ALI rats. Its mechanism might be associated with inhibiting TLR4 mRNA expressions, leading to decreased pro-inflammatory cytokines such as TNF-α and IL-β, elevated anti-inflammatory cytokine IL-10, and thereby, correcting unbalanced inflammation.