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Conjugated polymers (CPs) represent a promising platform for photocatalytic CO2 fixation owing to their suitable band structures that meet the requirements of the reduction potential of CO2 to value‐added fuels. However, the photocatalytic performance of CPs is rather restrained by the low charge transfer efficiency. Herein, we rationally designed three CPs with a more delocalized electronic transmission channel and planar molecular structure, which are regarded to evidently reduce the exciton binding energy (Eb) and accelerate the internal charge transfer process. Besides, the assembly of suitable electron‐output "tentacles" and cocatalysts on the surface of CPs could effectively facilitate interfacial electron delivery. Accordingly, the optimal P‐2CN exhibits an apparent quantum yield of 4.6 % at 420 nm for photocatalytic CO2 to CO. Further adjusting the amounts of cyano groups and cocatalysts, the CO selectivity could be obtained in the range of 0–80.5 %. [ABSTRACT FROM AUTHOR]

Conjugated polymers (CPs) have garnered increasing attention in the field of photocatalysis due to their stability and molecular tunability. Understanding the structure–property relationship in CPs and addressing appropriate molecular design strategies are pivotal to improving the photocatalytic performance of CPs. Herein, a new efficient cyano (CN) engineering approach was proposed to promote the photocatalytic performance of CPs, and three representative CP‐based photocatalysts with different CN contents were tailor‐made to investigate the relationship between CN functionalization and photocatalytic activity. A series of systematically experimental and theoretical studies reveal that CN functionalization contributes to strengthening the donor‐acceptor (D‐A) interaction, enhancing the light absorption ability, charge separation/transfer efficiency, and hydrophilicity of CPs, and also facilitating the output of separated photoinduced electrons from CPs to Pt cocatalyst. Thus, the dicyano‐functionalized polymer (P‐2CN) manifests an attractive photocatalytic performance in hydrogen production. This study provides a facile strategy to develop excellent CP‐based photocatalysts for solar fuel production. [ABSTRACT FROM AUTHOR]

Toxoplasma gondii (T.gondii) is a widespread protozoan with significant economic losses and public health importance. But so far, the protective effect of reported DNA-based vaccines fluctuates widely, and no study has demonstrated complete protection. This review provides an inclusive summary of T. gondii DNA vaccine antigens, adjuvants, and some other parameters. A total of 140 articles from 2000 to 2021 were collected from five databases. By contrasting the outcomes of acute and chronic challenges, we aimed to investigate and identify viable immunological strategies for optimum protection. Furthermore, we evaluated and discussed the impact of several parameters on challenge outcomes in the hopes of developing some recommendations to assist better future horizontal comparisons among research. In the coming five years of research, the exploration of vaccine cocktails combining invasion antigens and metabolic antigens with genetic adjuvants or novel DNA delivery methods may offer us desirable protection against this multiple stage of life parasite. In addition to finding a better immune strategy, developing better in silico prediction methods, solving problems posed by variables in practical applications, and gaining a more profound knowledge of T.gondii-host molecular interaction is also crucial towards a successful vaccine. [ABSTRACT FROM AUTHOR]

Conservation tillage is becoming increasingly attractive to farmers because it involves lower production costs than does conventional tillage. The long-term effects of sub-soiling tillage (ST), no tillage (NT), and conventional tillage (CT) on soil properties and crop yields were investigated over an 8-year period (2000-07). The study was conducted in a 2-crop-a-year region (Daxing) and a 1-crop-a-year region (Changping) of the Beijing area in China. At 0-0.30 m soil depth, water stability of macro-aggregates (>0.25 mm) was much greater for ST (22.1%) and NT (12.0%) than for CT in Daxing, and the improvements in Changping were 18.9% and 9.5%, respectively. ST and NT significantly (P< 0.05) improved aeration porosity by 14.5% and 10.6%, respectively, at Daxing and by 17.0% and 8.6% at Changping compared with CT treatment. Soil bulk density after 8 years was 0.8-1.5% lower in ST and NT treatments than in CT at both sites. Soil organic matter and available N and P followed the same order ST ≅ NT > CT at both sites. Consequently, crop yields in ST and NT plots were higher than in CT plots due to improved soil physical and chemical properties. Within the conservation tillage treatments, despite similar economic benefit, the effects on crop yields for ST were better than for NT. Mean (2000-07) crop yields for ST were 0.2% and 1.5% higher than for NT at Daxing and Changping, respectively. We therefore conclude that ST is the most suitable conservation tillage practice for annual 2-crop-a-year and 1-crop-a- year regions in the Beijing area. Additional keywords: sub-soiling tillage, soil fertility, aggregate stability, soil porosity, bulk density, yield., Introduction Conventional tillage has been practiced for centuries in China. This method is believed to reduce compaction, provide a favourable seed bed, increase root growth and development, control weeds, and [...]

Although well‐known that high current loan‐to‐value ratio (CLTV) is necessary for mortgage default, the amplifying effect of high payment‐to‐income ratios (PTI) that can force families to move has received limited attention. Using the 1985–2013 American Housing Survey panel, we show that high CLTV by itself has little effect on mobility, but high PTI prompts families to move and especially so when CLTV is high. Evidence also indicates that high PTI and CLTV discourage home maintenance. Our estimates suggest that loan modifications that lower PTI will likely be more effective at helping underwater families to remain in their homes and avoid mortgage default as compared to policies that lower CLTV. [ABSTRACT FROM AUTHOR]

Permanent raised beds have been proposed as a more productive and water-efficient alternative to the conventional system of flat, flood-irrigated bays for planting narrow-spaced crops in arid north-west China. Data from a field experiment (2005-2007) conducted in the Hexi Corridor at Zhangye, Gansu Province, China, were used to compared the effects of traditional tillage (TT), zero tillage (ZT), and permanent raised beds (PRB) on crop growth, yield, and water use in a spring wheat monoculture. The results show that PRB significantly (P < 0.05) increased soil water content to 0.30 m depth by 7.2-10.7% and soil temperature to 0.05 m depth by 0.2-0.9°C during the wheat-growing period relative to TT and ZT treatments. Bulk density in 0-0).10 m soil layer under PRB was also 5.8% less than for fiat planting treatments. Mean wheat yields over 3 years on PRB plots were slightly greater and furrow irrigation in permanent beds was particularly effective in increasing irrigation water use efficiency (~18%), compared with TT and ZT treatments. This increase in water use efficiency is of considerable importance for these arid areas where irrigation water resources are scarce. Additional keywords: bed planting, yield, water content, soil temperature, irrigation, arid areas., Introduction Water shortage is one of the major constraints to the production of agricultural crops in arid north-west China where average precipitation varies from 40 to 200 mm (Xie et [...]

Lead‐free halide perovskites and their variants have attracted great attention due to their non‐toxicity and good photophysical properties. Here, a series of undoped and antimony‐doped all‐inorganic, 0D, indium‐based perovskite variant nanocrystals (NCs): (RbxCs1−x)3InCl6 and (RbxCs1−x)3InCl6:Sb (0 ≤ x ≤ 1) NCs, is reported. Among them, Sb‐doped NCs exhibit green emission. Mixing Rb‐Cs NCs show the higher photoluminescence (PL) quantum efficiency (PLQE) and better stability than unalloyed NCs (x = 0 or 1). The effect of crystal size on PL property of (Rb0.75Cs0.25)3InCl6:Sb is analyzed in detail. More interestingly, In‐based perovskite variant NCs containing coordinated water are successfully synthesized by a two‐step method (variable temperature hot injection and saturated steam post treatment). The best PLQE of Sb‐doped Cs2InCl5(H2O) NCs reaches 95.5%, which is a new PLQE record for yellow emissive lead‐free perovskite and variant NCs. In addition, the emission mechanism is further clarified by temperature‐dependent PL and femtosecond transient absorption techniques. [ABSTRACT FROM AUTHOR]