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Sea surface temperature (SST) anomalies often display a tripole pattern in the North Atlantic Ocean. This study investigates the formation of large amplitude North Atlantic tripole SST anomaly pattern during boreal spring when the El Niño-Southern Oscillation (ENSO) and North Atlantic Oscillation (NAO) act individually and synthetically. It is found that the tripole SST anomalies have a larger amplitude when ENSO and NAO act together than when ENSO or NAO acts alone. The effects of ENSO are mainly in the tropics. The effects of NAO are larger in the high latitude. The large amplitude tripole SST anomaly pattern is associated with a similar tripole pattern in surface latent heat flux anomalies. Surface sensible heat flux and ocean horizontal advection also contribute to the high-latitude SST anomalies and have a supplementary effect on the mid-latitude SST anomalies. Latent heat lux anomalies are attributed to the effect of wind speed in the tropics and middle latitude and sea-air humidity difference in the high latitude. Sensible heat flux anomalies are mainly attributed to the effect of sea-air temperature difference. [ABSTRACT FROM AUTHOR]

Fibroblast growth factor 2 (FGF2) plays an important role in tumor angiogenesis. Humanized disulfide‐stable double‐chain antibody against fibroblast growth factor‐2 (anti‐FGF2 ds‐Diabody) is a small molecule antibody with good tissue permeability and low immunogenicity, which has potential in tumor‐targeted therapy. This study intended to investigate the effect of anti‐FGF2 ds‐Diabody on the migration and expression of programmed death‐ligand1 (PD‐L1) in hepatocellular carcinoma (HCC) cells. The anti‐FGF2 ds‐Diabody was expressed under methanol induction and purified with Ni2+‐affinity chromatography. Anti‐FGF2 ds‐Diabody significantly inhibited cell viability and proliferation in SK‐Hep1 and HepG2 cells as confirmed by CCK‐8 assays and colony formation assays. Western blot assays indicated that the proliferation of SK‐Hep1 and HepG2 cells was inhibited by anti‐FGF2 ds‐Diabody through inhibiting the phosphorylation activation of AKT and MAPK. The results of transwell and western blot assays showed that the migration and invasion of SK‐Hep1 and HepG2 cells were suppressed by anti‐FGF2 ds‐Diabody by affecting the epithelial‐mesenchymal transition (EMT) process. Meanwhile, anti‐FGF2 ds‐Diabody inhibited the expression of PD‐L1, and STAT3 participated in this process. Analysis of RT‐PCR and Western blot suggested that fibroblast growth factor receptor 4 inhibitor 1 (FGFR4‐IN‐1) suppressed the expression of PD‐L1, while STAT3 overexpression reversed this inhibitory effect. In addition, overexpression of STAT3 promoted migration and invasion and restored the suppressive effect of anti‐FGF2 ds‐Diabody on EMT. In conclusion, anti‐FGF2 ds‐Diabody could inhibit the expression of PD‐L1 and EMT of hepatoma cells through FGF2/FGFR4/STAT3 axis. These results suggested that anti‐FGF2 ds‐Diabody has potential clinical application in inhibiting metastasis and immune escape of hepatocellular carcinoma. [ABSTRACT FROM AUTHOR]

This study compares boreal spring surface air temperature (SAT) anomalies over mid- and high-latitude Eurasia in different categories of the North Atlantic tripole sea surface temperature (SST) anomalies for the period 1951–2018. It is found that Eurasian SAT anomalies depend largely upon the amplitude and polarity of the North Atlantic tripole SST anomalies (positive polarity for positive SST anomalies in the tropics and mid-latitude and negative SST anomalies in the subtropics). The main processes contributing to SAT anomalies vary with the region. In large amplitude positive tripole years, the SAT decreases in Europe and east of the Lake Baikal due to longwave radiation and sensible heat flux and increases in Siberia due to horizontal advection associated with anomalous northerlies. In large amplitude negative tripole years, the SAT increases in Europe and eastern Eurasia due to horizontal advection associated with anomalous southerlies. In small amplitude positive tripole years, the SAT increases in central Eurasia due to horizontal advection associated with mean and anomalous meridional winds. In small amplitude negative tripole years, the SAT decreases in southern central Eurasia, which is contributed by both longwave radiation and horizontal advection associated with anomalous northeasterlies. Atmospheric circulation influences SAT both directly through horizontal advection associated with anomalous winds and indirectly through shortwave radiation and in turn upward longwave radiation and sensible heat flux. The results reveal the necessity of distinguishing the amplitude and polarity of the North Atlantic SST anomalies in their impacts on climate variability. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A facile method was developed to synthesize regenerable and H 2 O resistance sorbent for Hg0 removal. • The Ag nanoparticles were successively confined inside the mesoporous channels of MCM-41 molecule sieve. • The nanoconfinement effect is conducive to excellent Hg0 removal performance and regeneration ability. • The high hydrophobicity of Ag/MCM-41 is beneficial for the resistance to H 2 O. Abstract A facile passivation treatment and amino functionalized method was developed for controllable synthesis of effective and water-resistant Ag/MCM-41 composite sorbent for Hg0 removal in natural gas. The Ag nanoparticles were successively confined inside the mesoporous channels of MCM-41 molecule sieve with an average diameter of 3 nm. The synthesized sorbent was found to achieve a complete removal of Hg0 at high space velocity of 50,000 h−1 in ambient temperature. At 5% breakthrough, the Hg0 capture capacity of 1% (wt%) silver loaded Ag/MCM-41 was as high as 6.64 mg·g−1, which is much higher than the sample of Ag loaded outside of the pore channels (S-Ag/MCM-41) and other existing commercial sorbents. The H 2 O has negligible inhibitory effect on Hg0 removal performance of Ag/MCM-41. In addition, the spent Ag/MCM-41 could be easily regenerated without significant performance degradation over five cycles. We considered the high Hg0 capture efficiency, large adsorption capacity and excellent regeneration performance of Ag/MCM-41 are contributed to the nanoconfinement effect of mesoporous channels of MCM-41 molecule sieve which effectively prevented the growth and agglomeration of Ag nanoparticles. The good hydrophobicity of Ag/MCM-41 is beneficial for the high resistance to H 2 O. This work represents a giant step toward the preparation of effective sorbent for practical applications of Hg0 removal in natural gas. [ABSTRACT FROM AUTHOR]

The silver loaded adsorbents has been demonstrated to be an exciting approach towards Hg 0 removal from natural gas streams, its Hg 0 removal efficiency and capacity is closely related to the valence state, particle size and dispersity of silver particles. This study focused on chemical reduction methods in aqueous solutions to synthesize Ag/4A zeolite, and the influences of ultrasonic and protective additives were investigated to reduce the size of silver particles. The characterization results showed that silver particles are loaded on the surface of 4A zeolite with highly dispersed elemental form, ultrasonic and addition of stearic acid as protective additives are the effective ways to produce small nano-scale silver particles close to 15 nm. Meanwhile, the silver particles on the surface of Ag/4A zeolite are the active sites for Hg 0 adsorption which can react with Hg 0 to form Ag-Hg amalgam alloy. The silver lattices disappeared from the outer boundary to the interior of the particles after Hg 0 adsorption, which indicated that the Hg 0 firstly reacts with the nano-scale silver on the surfaces and then gradually penetrates into the interior of silver particles. The Hg 0 removal efficiency of prepared Ag/4A zeolite adsorbents was higher than 96% after 200 min adsorption at 30 °C, and adsorption capacity reached to 5.985 mg/g. Furthermore, the regeneration and reutilization results indicated that the Hg 0 adsorption performance remained stable after 5 reuse cycles. [ABSTRACT FROM AUTHOR]

A bench-scale fixed bed reactor was used to study the influences of water vapor and fly ash on Hg 0 removal efficiency over CeO 2 -modified semi-coke adsorbent (Ce/SC). Adsorption results showed that the mercury removal efficiency of Ce/SC decreased by 30% in the presence of 10% water vapor, and the introduction of 0.5 g fly ash had no significant effect on the Hg 0 removal efficiency of Ce/SC. In the condition of water vapor and fly ash coexisted, the Hg 0 removal efficiency of Ce/SC decreased by only 15%, indicated that the fly ash slowed down the inhibitory effects of water vapor on Hg 0 removal efficiency over Ce/SC, which is mainly due to the interaction between water vapor and Fe 2 O 3 in the fly ash to form Fe-OH groups, furthermore, γ-Fe 2 O 3 exhibited higher Hg 0 removal performance than α-Fe 2 O 3 . Hydrogen temperature-programmed reduction (H 2 -TPR) revealed that the oxidation activity and capacity of α-Fe 2 O 3 and γ-Fe 2 O 3 increased significantly after water vapor treatment. X-ray photoelectron spectroscopy (XPS) results showed that the Fe-OH content of α-Fe 2 O 3 and γ-Fe 2 O 3 increased from 37.97% and 15.99% to 44.56% and 43.39%, while the lattice oxygen content decreased from 26.53% and 82.46% to 19.08% and 46.49%, respectively. Density functional theory (DFT) calculations revealed that H 2 O molecules can be dissociated on both α-Fe 2 O 3 (1 0 4) and γ-Fe 2 O 3 (2 2 0) surfaces to form H atoms and OH fragments, the H atoms bound with O atoms in Fe-O groups of both α-Fe 2 O 3 (1 0 4) and γ-Fe 2 O 3 (2 2 0) surfaces, and the OH fragments associated with the adjacent iron atoms of α-Fe 2 O 3 (1 0 4) surface or Fe-O groups of γ-Fe 2 O 3 (2 2 0) surface to form Fe-OH. The formation of Fe-OH groups increased the oxidation activity and Hg 0 removal efficiency of Fe 2 O 3 . [ABSTRACT FROM AUTHOR]

Ultrathin two-dimensional (2D) metal–organic framework (MOF) nanosheets are promising advanced materials due to their particularly thin thickness and exposed active sites. The difficulty in the controlled synthesis of 2D MOFs and the limited effective synthetic routes greatly limit further extension of their applications. In this work, a solution-processed approach based on the direction of sodium dodecyl sulfate (SDS) is developed, by which a series of well-dispersed square non-layered MOF and layered MOF nanosheets have been synthesized successfully. Dynamic light scattering analysis suggests that the negative charge of SDS induces the pre-assembly of metal ions, which further leads to the 2D self-assembly process in the growth of MOF nanocrystals. The approach would be sure to push forward the effective shape control and mass production of MOF 2D nanomaterials and stimulate further research in the fields of electronic nanodevices, energy storage, catalysis and biosensing. [ABSTRACT FROM AUTHOR]

The present study investigates the dependence of the northern tropical Atlantic (NTA) sea surface temperature (SST) response to El Niño and La Niña events on the decay time and amplitude of tropical Pacific SST anomalies. It is found that the NTA SST response to La Niña events displays a notable difference between late and early decaying events, similar to that in response to El Niño events, but with a weaker signal. Latent heat flux is a dominant term in the NTA SST change in preceding winter-early spring in both El Niño and La Niña events and in the difference of the NTA SST anomaly between late and early decaying El Niño and La Niña events. The zonal and meridional advections have an opposite effect on the NTA SST warming in late decaying El Niño events. Although the warming in the NTA region is similar in late decaying moderate and strong El Niño events, the distribution of the SST anomalies in the mid-latitude North Atlantic Ocean shows a notable difference between the two types of late decaying El Niño events. The SST anomalies also display difference in the early decaying weak and moderate El Niño events. Surface heat flux differences are largely attributed to wind differences. [ABSTRACT FROM AUTHOR]

Abstract: A general, efficient iron‐catalyzed α‐alkylation of nitriles with primary alcohols through a hydrogen‐borrowing pathway has been developed, allowing a wide variety of alkylated nitriles to be readily accessible. Detailed mechanistic studies suggest that the reaction proceeds via an olefin intermediate with the turnover rate limited by the hydrogenation of the olefin with an iron hydride. Apart from participating in the alkylation, the nitrile is found to play an important role in promoting the formation of and stabilizing the active catalytic species. [ABSTRACT FROM AUTHOR]

Cationic liposome delivery of interfering RNA (shRNA) plays an important role in tumor therapy. The cyclic Arg-Gly-Asp (cRGD) modified cationic liposomes (cRGD-CL) were designed for targeted delivery of ONECUT2 (OC-2) shRNA (pshOC-2) to breast cancer cells. The characterization analysis of cationic liposome showed that the prepared cRGD-CL/pshOC-2 lipoplexes had uniform particle size (150 ± 1.02 nm), moderate zeta potential (19.8 ± 0.249 mV) and high encapsulation efficiency (up to 96%). The results of flow cytometer showed that the introduction of cRGD could significantly promote the liposomes targeting tumor cells. In MCF-7 cells, the pshOC-2 could down-regulate expression of OC-2 and result in cell apoptosis, inhibition of the wound healing, migration and cell colony formation, in which the signal pathways of Bcl-xL, Bcl-2 were inhibited and the signal pathways of Bax and Cleaved Caspase-3 were promoted. In MCF-7 xenograft mice, intravenous administration of cRGD-CL/pshOC-2 lipoplexes could effectively reduce the expression of OC-2 in tumors and result in apparently antitumor effects, which suggested that the lipoplexes might be deeply penetrated into tumor through receptor-mediated transcytosis. The results revealed that the cationic liposome (cRGD-CL) was an effective delivery system for OC-2 shRNA, which might be an effective therapeutic candidate for breast cancer. [ABSTRACT FROM AUTHOR]

A CoFe 2 O 4 /MEG solid-phase extraction combined with high performance liquid chromatography was used for determination of 8 biogenic amines (Bas) in canned Spanish mackerel products. A new comprehensive evaluation system, including dietary exposure, food safety index, chemical quality index and biogenic amine index, was used for investigating the pollution distribution, exposure and health assessment of BAs in four sea areas/provinces of China. The pollution levels in the Yellow Sea-Jiangsu, Bohai Sea-Shandong, Yellow and Bohai Sea-Liaoning regions were equivalent, with ∑8BAs equalling 34.7–36.5 mg/kg, while in the South China Sea-Guangdong region ∑8BAs was lowest at 18.9 mg/kg. The concentration range of ∑8BAs and ∑4BAs were ND (not detected)-113 mg/kg and ND-80.8 mg/kg, respectively. All results showed that the main components of BAs were putrescine, histamine, and spermine, with detection rates ranging from 23.1% to 42.3%. The dietary exposure level range of 8 BAs was 85.8–266 μg∙kg−1∙d−1, IFSc was 0.00800–0.0248, CQI values range in the four regions was 1.21–3.93, with a mean CQI of 1.98. The total value of BAI ranges ND-0.840 mg/kg, with a mean BAI of 20.3 mg/kg. Statistical analysis showed that the overall health risk of BAs exhibits different trends in terms of gender, age, and region. [Display omitted] • A new quantitative detection method for 8 BAs in canned Spanish mackerel. • Classification and evaluation in different sea areas, gender, age, and region. • Comprehensive health risk assessment based on dietary exposure, IFSc, CQI, and BAI. [ABSTRACT FROM AUTHOR]

• Layered CALB-CLEAs were applied to DKR of chiral amines. • Ultra-high yield was achieved without the aid of additive. • Mild microwave strategy to improve the DKR efficiency was discussed. • Aliphatic amines also can be efficiently converted to enantiopure products. Acquisition of chiral amines is a very important item in scientific research. Chemoenzymatic catalyst combination of Pd nanoparticles supported on the external surface of the ethylenediamine-functionalized MIL-101 (Pd@ED-MIL-101) with layered cross-linked enzyme aggregates of Candida antarctica lipase B (CALB-CLEAs) was established for the first time. This combination served as an ultra-efficient chemoenzymatic catalyst system for one-pot dynamic kinetic resolution (DKR) of rac -1-phenylethylamine leading to optically pure product (>99% ee value) with almost full conversion and excellent selectivity (>99%) without the aid of any additive. Significantly, aliphatic amines can be also efficiently converted to enantiomerically pure products, making this robust and heterogeneous combination one of the most powerful chemoenzymatic platforms for microwave-assisted one-pot DKR of amines available up to now. [ABSTRACT FROM AUTHOR]

The first manganese‐catalyzed oxidation of organosilanes to silanols with H2O2 under neutral reaction conditions has been accomplished. A variety of organosilanes with alkyl, aryl, alknyl, and heterocyclic substituents were tolerated, as well as sterically hindered organosilanes. The oxidation appears to proceed by a concerted process involving a manganese hydroperoxide species. Featuring mild reaction conditions, fast oxidation, and no waste byproducts, the protocol allows a low‐cost, eco‐benign synthesis of both silanols and silanediols. [ABSTRACT FROM AUTHOR]

The first manganese‐catalyzed oxidation of organosilanes to silanols with H2O2 under neutral reaction conditions has been accomplished. A variety of organosilanes with alkyl, aryl, alknyl, and heterocyclic substituents were tolerated, as well as sterically hindered organosilanes. The oxidation appears to proceed by a concerted process involving a manganese hydroperoxide species. Featuring mild reaction conditions, fast oxidation, and no waste byproducts, the protocol allows a low‐cost, eco‐benign synthesis of both silanols and silanediols. [ABSTRACT FROM AUTHOR]

Introduction: The Joint United Nations Programme on human immunodeficiency virus (HIV)/acquired immune deficiency syndrome has proposed the 90-90-90 targets by 2020. Human immunodeficiency virus epidemic is spreading rapidly among men who have sex with men (MSM) in China. This study investigates how the scale-up of HIV testing and treatment in achieving the targets and its cost-effectiveness.Methods: We constructed a compartmental model to forecast the HIV epidemic in Chinese MSM based on various "test-and-treat" scale-up scenarios. We assessed their cost effectiveness based on the cost for each HIV infection, death, and disability-adjusted life years (DALYs) prevented by the scale-up.Results: If the current epidemic continued, HIV prevalence among Chinese MSM would increase from 9.2% in 2016 to 12.6% (9.2-15.6%) in 2020 and 16.2% (11.3-20.0%) in 2025. By 2020, 49.2% of infected MSM would be diagnosed and 40.1% of whom on treatment, falling short of the 90-90-90 targets, so would be even by 2025. To achieve these targets by 2020, additional 850,000 HIV screening tests and 112,500 person-years of antiretroviral treatment (ART) annually are necessary. This spending is US $478 million during 2016 to 2020, which almost tripled the status quo. However, by delaying to 2025, an investment of US $1210 million over 2016 to 2025 corresponding to 52% increase to the status quo, will enable extra 340,000 HIV screening tests and 60,000 person-year on ART annually. In both scenarios, the incremental cost-effectiveness ratio was US $733 to 960 for each DALY prevented, indicating highly cost-effective scenarios.Conclusions: Achieving the 90-90-90 targets by 2020 requires steep increase in investment, but delaying the targets to 2025 is practical and cost-effective. [ABSTRACT FROM AUTHOR]

Summary: Background: Asian HIV epidemics are concentrated among particular behavioural groups, but large variations exist in epidemic types, timing, and geographical spread between countries and within countries, especially in China. We aimed to understand the complexity of HIV epidemics in China by systematically analysing prevalence trends by data source, region, population group, and time period. Methods: We collected HIV prevalence data from official national sentinel surveillance sites at the provincial level from Jan 1, 1995, to Dec 31, 2010. We also searched PubMed, VIP Chinese Journal Database (VIP), China National Knowledge Infrastructure, and Wanfang Data from Jan 1, 1990, to Dec 31, 2012, for independent studies of HIV prevalence. We integrated both sets of data, and used an intraclass correlation coefficient test to assess the similarity of geographical pattern of HIV disease burden across 31 Chinese provinces in 2010. We investigated prevalence trends (and 95% CIs) to infer corresponding incidence by region, population group, and year. Findings: Of 6850 articles identified by the search strategy, 821 studies (384 583 drug users, 52 356 injecting drug users, 186 288 female sex workers, and 87 834 men who have sex with men) met the inclusion criteria. Official surveillance data and findings from independent studies showed a very similar geographical distribution and magnitude of HIV epidemics across China. We noted that HIV epidemics among injecting drug users are decreasing in all regions outside southwest China and have stabilised at a high level in northwest China. Compared with injecting drug users, HIV prevalence in female sex workers is much lower and has stabilised at low levels in all regions except in the southwest. In 2010, national HIV prevalence was 9·08% (95% CI 8·04–10·52) in injecting drug users and 0·36% (0·12–0·71) in female sex workers, whereas incidence in both populations stabilised at rates of 0·57 (0·43–0·72) and 0·02 (0·01–0·04) per 100 person-years, respectively. By comparison, HIV prevalence in men who have sex with men increased from 1·77% (1·26–2·57) in 2000, to 5·98% (4·43–8·18) in 2010, with a national incidence of 0·98 (0·70–1·25) per 100 person-years in 2010. We recorded strong associations between HIV prevalence among at-risk populations in each province, supporting the existence of overlap in risk behaviours and mixing among these populations. Interpretation: HIV epidemics in China remain concentrated in injecting drug users, female sex workers, and men who have sex with men. HIV prevalence is especially high in southwest China. Sex between men has clearly become the main route of HIV transmission. Funding: The World Bank Group, the Australian Research Council, the University of New South Wales, and Chinese Center for Disease Control and Prevention. [ABSTRACT FROM AUTHOR]

• Sn-doped Co 3 O 4 nanorods was used as CO oxidation catalyst. • Only Co2+ in the lattice of Co 3 O 4 were substituted by Sn4+. • This catalyst displayed low-temperature activity (T 100 ∼ −100 °C). • This catalyst possessed excellent stability at ambient temperature. Catalytic oxidation of CO at ambient temperature is an important reaction for many environmental applications. Here, we employed a defect engineering strategy to design an extraordinarily effective Sn-doped Co 3 O 4 nanorods (NRs) catalyst for CO oxidation. Our combined theoretical and experimental data demonstrated that Co2+ in the lattice of Co 3 O 4 were substituted by Sn4+. Based on a variety of characterizations and kinetic studies, this catalyst was found to combine the advantages of the nanorod-like morphology for largely exposing catalytically active Co3+ sites and the promotional effect of Sn dopant for adjusting the textural/redox properties. Additionally, the Sn-substituted Co 3 O 4 NRs can be further activated via heat treatment to achieve low-temperature CO oxidation (T 100 ∼ −100 °C) with excellent stability at ambient temperature. This study reveals the importance of Sn-substitution of inactive Co2+ in Co 3 O 4 and provides an ultra-efficient catalyst for CO oxidation, making this robust material one of the most powerful catalysts available up to now. [ABSTRACT FROM AUTHOR]