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The Salt Substitute and Stroke Study is an ongoing 5-year large-scale cluster randomized trial investigating the effects of potassium-enriched salt substitute compared to usual salt on the risk of stroke. The study involves 600 villages and 20,996 individuals in rural China. Intermediate risk markers were measured in a random subsample of villages every 12 months over 3 years to track progress against key assumptions underlying study design. Measures of 24-hour urinary sodium, 24-hour urinary potassium, blood pressure and participants' use of salt substitute were recorded, with differences between intervention and control groups estimated using generalized linear mixed models. The primary outcome of annual event rate in the two groups combined was determined by dividing confirmed fatal and non-fatal strokes by total follow-up time in the first 2 years. The mean differences (95% CI) were -0.32 g (-0.68 to 0.05) for 24-hour urinary sodium, +0.77 g (+0.60 to +0.93) for 24-hour urinary potassium, -2.65 mmHg (-4.32 to -0.97) for systolic blood pressure and +0.30 mmHg (-0.72 to +1.32) for diastolic blood pressure. Use of salt substitute was reported by 97.5% in the intervention group versus 4.2% in the control group (P<.0001). The overall estimated annual event rate for fatal and non-fatal stroke was 3.2%. The systolic blood pressure difference and the annual stroke rate were both in line with the statistical assumptions underlying study design. The trial should be well placed to address the primary hypothesis at completion of follow-up. [ABSTRACT FROM AUTHOR]

Lowering sodium intake with a reduced-sodium, added potassium salt substitute has been proved to lower blood pressure levels. Whether the same strategy will also reduce the risks of vascular outcomes is uncertain and controversial. The SSaSS has been designed to test whether sodium reduction achieved with a salt substitute can reduce the risk of vascular disease. The study is a large-scale, open, cluster-randomized controlled trial done in 600 villages across 5 provinces in China. Participants have either a history of stroke or an elevated risk of stroke based on age and blood pressure level at entry. Villages were randomized in a 1:1 ratio to intervention or continued usual care. Salt substitute is provided free of charge to participants in villages assigned to the intervention group. Follow-up is scheduled every 6months for 5years, and all potential endpoints are reviewed by a masked adjudication committee. The primary end point is fatal and nonfatal stroke, and the 2 secondary endpoints are total major cardiovascular events and total mortality. The study has been designed to provide 90% statistical power (with 2-sided α = .05) to detect a 13% or greater relative risk reduction for stroke. The power estimate assumes a primary outcome event rate of 3.5% per year and a systolic blood pressure difference of 3.0mm Hg between randomized groups. Recruitment is complete and there are 20,996 participants (about 35 per village) that have been enrolled. Mean age is 65years and 49% are female. There were 73% enrolled on the basis of a history of stroke. The trial is well placed to describe the effects of salt substitution on the risks of vascular disease and death and will provide important policy-relevant data. [ABSTRACT FROM AUTHOR]

We reconstructed a 500-year long winter (November to February) temperature series with a yearly resolution in southern China. The series is based on six types of proxies extracted from historical documents, including the southern limits of frost disaster, freezing disaster and snow, along with snowfall days and the first/last frost disaster dates. In the reconstruction, linear regression models are established among each proxy and regional winter temperature. Variance matching, minimum selection, and envelope analysis methods are performed to eliminate non-homogeneous effects because of different proxy types, missing data, and the changing amount of records. Compared with the average temperatures during 1851–1950, the reconstruction shows that southern China experienced a cold period in the first 40 years of the sixteenth century with an average of −0.40 °C with frequent extremes. An upturning occurred during the 1540s to mid-1560s, followed by a stable phase until the 1620s. Then the temperature started to fall from the 1630s and reached its lowest in 1660, where it dropped to −2.01 °C. Moreover, the mean value was −0.49 °C between the years 1648–1697, which was the coldest 50 years over the last five centuries. The temperatures during the eighteenth century to the middle of the twentieth century was characterized by annual to decadal fluctuations, with two moderately warm intervals in the 1770s and 1840s–1850s, as well as three moderately cold intervals in 1790s, 1830s, and 1870s to the mid-1890s. Over the recent century, the warming rate since 1901 was 0.56 °C/100a, whereas the temperature reached 0.32 °C/10a after 1979. The hottest five years during the last five centuries all occurred after 1990. [ABSTRACT FROM AUTHOR]

Abstract Proxy-based reconstructions of the Asian Summer Monsoon exhibit variability over multiple scales, from inter-annual to centennial. The relationship between East Asia Summer Monsoon (EASM) variability and the El Niño-Southern Oscillation (ENSO) over the last millennium remains unclear and a focus of current research. This study investigates this relationship using observations, reanalysis data, proxy-based reconstructions, and a control simulation using the Community Earth System Model (CESM). The results derived from both the observation/reanalysis/proxy-based reconstruction and the simulation show consistently that the relationship between EASM strength and Niño3.4 SST is divergent. The observation/reanalysis data illustrate strong negative correlations between Niño3.4 SST and EASM strength at an annual scale in the 1920s-1930s and 1980s-1990s, with weak correlations during other periods. The proxy-based reconstruction demonstrates strong negative correlations at inter-decadal scales from the 1360s to the 1530s, with either weak correlations or positive correlations during other periods. Moreover, the simulations reveal positive correlations in some periods and negative or weak correlations in other periods. The simulations demonstrate that the divergent relationship may be derived from multi-decadal variations in Pacific SST caused by internal variability in the climate system, likely due to the Inter-decadal Pacific Oscillation (IPO). The EASM variation is usually in (out of) phase with Niño3.4 SST during the positive (negative) phase of the IPO. In the positive phase of the IPO, there is a tripolar pattern expressed in a cyclone-anticyclone-cyclone arrangement at pressure level of 850 hPa from the tropics to mid-latitudes over the northwest Pacific. Warming of the Niño3.4 strengthens the tropical cyclone by weakening the trade winds and subsequently strengthening the subtropical anticyclone, leading to a strong Meiyu front, which suggests a strong EASM. However, in the negative phase of the IPO, a huge cyclone occupies the northwest Pacific. Warming of the Niño3.4 strengthens the cyclone by weakening the trade winds, which leads to a weak Meiyu front, which suggests a weak EASM. These results may be helpful in further understanding the mechanisms through which the ENSO and IPO impact the atmospheric circulations in the Asian Pacific, especially regarding the long-term variations in EASM at inter-annual to inter-decadal scales. [ABSTRACT FROM AUTHOR]

One of the main obstacles that hamper the application of zeolites is the high consumption of expensive structure-directing agent. Herein, we reported the mechanochemisty-mediated solventless synthesis of AlPO 4 -11 aluminophosphate molecular sieve with low dosage of diisopropylamine (DIPA) as the structure-directing agent. The influences of DIPA/Al 2 O 3 ratio, fluoride ions, seed crystals and high-energy mechanochemical pretreatment on the synthesis of AEL-type zeolite were investigated in detail. Both DIPA and fluoride ions are indispensable for the successful synthesis of AEL phase. The resultant AEL molecular sieves were characterized by XRD, SEM, TG-DTA, CHN elements analysis, and N 2 physisorption. The results indicate that the introduction of seed crystals cannot improve the phase purity and crystallinity of the resulting products. On the other hand, high-energy mechanochemical pretreatment not only can affect the morphology of AEL zeolite, but more importantly, can also reduce the consumption of structure-directing agent. [ABSTRACT FROM AUTHOR]

It still remains uncertainty whether China's future investment is conducive to carbon reduction of Belt and Road (B&R) region or not. Here, the possible impact of China's investment was revealed by comparing the CO 2 emissions of B&R region in different Chinese investment scenarios. The results showed that CO 2 emissions of B&R region will cumulatively increase by 1973 Gt in 2018–2100 in the "No-Chinese Investment Scenario (NIS)". Regionally, the India (IND), Middle East Central Asia (MECAsia), and Southeast Asia and its surrounding (SEAsia) has the largest increment. Comparing with the NIS, the CO 2 emissions of B&R region will cumulatively decrease by 44.16 Gt and 79.48 Gt, respectively, in the "Business-as-usual Chinese Investment Scenario (BIS)" and "Strengthening Chinese Investment Scenario (SIS)". Regionally, the cumulative CO 2 emissions of all subregions will decrease in BIS and SIS, of which SEAsia and MECAsia have the largest decrement. Technique and structural effects of China's investment have positive impact on cumulative CO 2 emission reduction of B&R region, especially in the structural effect. The scale effect has the negative contribution, but it cannot neutralize the positive impact induced from technique and structural effects. As a result, China's future investment is conductive to reducing CO 2 emission of B&R region and holding the temperature increase below 2 °C. [ABSTRACT FROM AUTHOR]

Large-scale palaeoclimate reconstructions can be very sensitive to the proxy records they are based on, and hence to the criteria used to select proxy records. Data selection rarely follows objective criteria that are applicable to all types of proxies, including both low- and high-resolution records. Thus, there is a need for a uniform and transparent approach to assess the suitability of input proxy data for a reconstruction. Here, we develop classification criteria that are applicable to multiple proxy types and evaluate different selection strategies using a network of 62 millennium-long terrestrial hydroclimate proxy records from Monsoon Asia. Our results reveal that robust evidence for a coherent climate signal and high dating accuracy are important criteria for benchmarking the suitability of each proxy record. We determine these criteria by reviewing the literature for each record (rather than screening against instrumental data). We show that the proposed selection approach can yield a network with a stronger common signal. By evaluating the uncertainty and centennial variability of composite reconstructions, from differently selected subsets of the proxy network, it appears beneficial to use suitable proxies stemming from different archives, as well as having a dense network of proxy sites. We suggest that future large-scale palaeoclimate reconstructions might be improved by evaluating proxy networks according to the universal categories presented here and, if indicated, removing less suitable records. This will strengthen the climate signal in the final reconstruction, allowing more precise inferences about past climate variability and more robust comparisons with climate model simulations. • Suitability of proxy records should be estimated based on literature review. • Semi-quantitative criteria: evidence for climate signal and dating accuracy. • Proposed selection approach can yield a network with a stronger common signal. • Multi-proxy approach is beneficial to preserve various frequency domains. [ABSTRACT FROM AUTHOR]