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【Background】Maize production in Jilin province of China needs irrigation because precipitation and antecedent soil water in its growth season cannot meet its demand. Although the impact of water stress in maize growth has been well documented, how its physiological characteristics respond to irrigation amount is an issue remaining obscure for maize production in Jilin province. 【Objective】This paper aims to elucidate irrigation-water use efficiency of the maize under different irrigation amounts, with a view to improve water use efficiency without compromising yield in the semi-arid areas in the west of the province. 【Method】A two-year field experiment was conducted with the variety Huanong 887 as the model plant. We compared four irrigation amounts: 500 (CK), 900 (Q1), 1 700 (Q2) and 2 500 m3/hm2 (Q3), and in each treatment we measured the accumulation of nitrogen, grain filling, activities of nitrogen metabolizing enzymes in leaves, as well as root injury level. 【Result】①The average grain-filling rate, 100-grain weight and root injury level all increased with the irrigation amount, but their values in Q2 and Q3 were significantly higher than those in Q1 and CK. ②Compared to Q1 and CK, Q2 and Q3 significantly increased nitrogen content in grains, stems and leaves. ③With the increase in irrigation amount, the activities of glutamine synthetase (GS) in the leaves increased, while the activities of glutamate dehydrogenase (GDH) in the leaves decreased. ④The yield increased with irrigation amount, especially in Q2 and Q3. ⑤No significant difference in yield and physiological traits was found between Q2 and Q3. 【Conclusion】Soil moisture is an important factor limiting growth and development of maize in the semi-arid areas in the western Jilin province. With the increase in irrigation amount, the yield, average grain-filling rate, 100-grain weight, root injury level, nitrogen accumulation and GS activity in the leaves all increased, while the activity of GDH in the leaves decreased. The physiological traits were significantly correlated with the yield. When the irrigation amount was 1 700 m3/hm2, the grain-filling rate, root injury level, nitrogen accumulation, nitrogen metabolizing enzyme activity in the leaves were optimal, giving the highest yield. It thus can be used as the reference irrigation strategy for maize production for the studied areas.

Abstract Background In China, high prevalence of HBV and HCV parallels with the growing epidemic of syphilis and HIV in the general population poses a great threat to blood safety. This study investigated the prevalence of serologic markers for transfusion transmissible infections (TTIs) among four Chinese blood centers. Methods We examined whole blood donations collected from January 2000 through December 2010 at four Chinese blood centers. Post-donation testing of TTIs (HIV, HBV, HCV and syphilis) were conducted using two different enzyme-linked immunosorbent assay kits for each seromarker. The prevalence of serologic markers for TTIs (%) was calculated and additional analysis was conducted to examine donor characteristics associated with positive TTIs serology. Results Of the 4,366,283 donations, 60% were from first-time donors and 40% were from repeated donors. The overall prevalence of HIV, HBsAg, HCV and syphilis was 0.08%, 0.86%, 0.51% and 0.47%, respectively. The prevalence profile of TTIs varied among different blood centers and appeared at relatively high levels. Overall, the prevalence of HBsAg and HCV demonstrated a decline trend among four blood centers, while the prevalence of HIV and syphilis displayed three different trends: constantly steady, continually increasing and declining among different centers. Conclusions This study reflects the risk of TTIs has been greatly reduced in China, but blood transfusion remains an ongoing risk factor for the spread of blood-borne infections, and further work and improvements are needed to strengthen both safety and availability of blood in China.

Compositional engineering has been used to overcome difficulties in fabricating high-quality phase-pure formamidinium perovskite films together with its ambient instability. However, this comes alongside an undesirable increase in bandgap that sacrifices the device photocurrent. Here we report the fabrication of phase-pure formamidinium-lead tri-iodide perovskite films with excellent optoelectronic quality and stability. Incorporation of 1.67 mol% of 2D phenylethylammonium lead iodide into the precursor solution enables the formation of phase-pure formamidinium perovskite with an order of magnitude enhanced photoluminescence lifetime. The 2D perovskite spontaneously forms at grain boundaries to protect the formamidinium perovskite from moisture and suppress ion migration. A stabilized power conversion efficiency (PCE) of 20.64% (certified stabilized PCE of 19.77%) is achieved with a short-circuit current density exceeding 24 mA cm-2 and an open-circuit voltage of 1.130 V, corresponding to a loss-in-potential of 0.35 V, and significantly enhanced operational stability.

Incorporating narrow-bandgap near-infrared absorbers as the third component in a donor/acceptor binary blend is a new strategy to improve the power conversion efficiency (PCE) of organic photovoltaics (OPV). However, there are two main restrictions: potential charge recombination in the narrow-gap material and miscompatibility between each component. The optimized design is to employ a third component (structurally similar to the donor or acceptor) with a lowest unoccupied molecular orbital (LUMO) energy level similar to the acceptor and a highest occupied molecular orbital (HOMO) energy level similar to the donor. In this design, enhanced absorption of the active layer and enhanced charge transfer can be realized without breaking the optimized morphology of the active layer. Herein, in order to realize this design, two new narrow-bandgap nonfullerene acceptors with suitable energy levels and chemical structures are designed, synthesized, and employed as the third component in the donor/acceptor binary blend, which boosts the PCE of OPV to 11.6%.

Covalent organic frameworks (COFs) have recently received significant attention as effective photocatalysts which rely on the selected photoactive building units. Benzoselenadiazole is one such unit that enables swift light-induced charge transfer and therefore could be used to construct COFs for photocatalytic conversions. Herein, in the presence of an organobase, 1,3,5-triformylphloroglucinol (Tp) and 4,4′-(benzoselenadiazole-4,7-diyl)dianiline (BSe) are adopted to construct a highly crystalline COF, TpBSe-COF. As designed, TpBSe-COF could implement the blue light photocatalytic conversion of organic sulfides to sulfoxides more adequately than TpDT-COF. Conspicuously, introducing the benzoselenadiazole unit into COFs can broaden the visible light absorption and accelerate electron transfer. Moreover, the synergy between TpBSe-COF and TEMPO (2,2,6,6-tetramethylpiperidine-N-oxyl) for selective photocatalysis could significantly improve the conversions of organic sulfides to sulfoxides with molecular oxygen. This work suggests the vast potential of benzoselenadiazole COFs in selective photocatalytic conversions. [ABSTRACT FROM AUTHOR]

Drip irrigation has a close relationship with the growth and development of maize grains and yield formation in semiarid areas. To explore the response mechanism of grain yield formation to drip irrigation quotas, a 2-year pond planting experiment was conducted under controlled conditions, by using two maize varieties with differences in drought resistance as experimental materials. Six treatments were set up, including CK1 (drought-resistant variety, 500 mm), T1 (drought-resistant variety, 350 mm), T2 (drought-resistant variety, 200 mm), CK2 (drought-sensitive variety, 500 mm), T3 (drought-sensitive variety, 350 mm), and T4 (drought-sensitive variety, 200 mm). The changes in maize grain filling characteristics, related hormones, enzyme activity related to starch synthesis, sugars and amino acids contents, and yield were analysed. The results showed that 100-grain weight at different filling times, filling rate, average filling rate, auxin, cytokinin, acid sucrose invertase, sucrose synthase, starch synthase, and adenosine diphosphate glucose pyro phosphorylase activities in maize grains decreased and the abscisic acid content and content of various amino acids and sugars in grains increased with the decrease in drip irrigation quota. The percentage of changes in drought-sensitive maize varieties was relatively high. The maize yield decreased with the decrease in drip irrigation quota. In summary, there was no significant difference in grain filling characteristics, hormone content, starch synthesis enzyme activity, and yield between maize treated with T1 (drought-resistant variety, 350 mm) and the control treatment. This effectively maintained grain growth and yield formation, achieving the goal of water saving and stable yields. [ABSTRACT FROM AUTHOR]