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71.
The record efficiency of the state‐of‐the‐art polymer solar cells (PSCs) is rapidly increasing, due to the discovery of high‐performance photoactive donor and acceptor materials. However, strong questions remain as to whether such high‐efficiency PSCs can be produced by scalable processes. This paper reports a high power conversion efficiency (PCE) of 13.5% achieved with single‐junction ternary PSCs based on PTB7‐Th, PC71BM, and COi8DFIC fabricated by slot‐die coating, which shows the highest PCE ever reported in PSCs fabricated by a scalable process. To understand the origin of the high performance of the slot‐die coated device, slot‐die coated photoactive films and devices are systematically investigated. These results indicate that the good performance of the slot‐die PSCs can be due to a favorable molecule‐structure and film‐morphology change by introducing 1,8‐diiodooctane and heat treatment, which can lead to improved charge transport with reduced carrier recombination. The optimized condition is then used for the fabrication of large‐area modules and also for roll‐to‐roll fabrication. The slot‐die coated module with 30 cm2 active‐area and roll‐to‐roll produced flexible PSC has shown 8.6% and 9.6%, respectively. These efficiencies are the highest in each category and demonstrate the strong potential of the slot‐die coated ternary system for commercial applications.  相似文献   
72.
Herein, a new P2‐type layered oxide is proposed as an outstanding intercalation cathode material for high energy density sodium‐ion batteries (SIBs). On the basis of the stoichiometry of sodium and transition metals, the P2‐type Na0.55[Ni0.1Fe0.1Mn0.8]O2 cathode is synthesized without impurities phase by partially substituting Ni and Fe into the Mn sites. The partial substitution results in a smoothing of the electrochemical charge/discharge profiles and thus greatly improves the battery performance. The P2‐type Na0.55[Ni0.1Fe0.1Mn0.8]O2 cathode delivers an extremely high discharge capacity of 221.5 mAh g?1 with a high average potential of ≈2.9 V (vs Na/Na+) for SIBs. In addition, the fast Na‐ion transport in the P2‐type Na0.55[Ni0.1Fe0.1Mn0.8]O2 cathode structure enables good power capability with an extremely high current density of 2400 mA g?1 (full charge/discharge in 12 min) and long‐term cycling stability with ≈80% capacity retention after 500 cycles at 600 mA g?1. A combination of electrochemical profiles, in operando synchrotron X‐ray diffraction analysis, and first‐principles calculations are used to understand the overall Na storage mechanism of P2‐type Na0.55[Ni0.1Fe0.1Mn0.8]O2.  相似文献   
73.
The concept of drug repositioning has recently received considerable attention in the field of oncology. In the present study, we propose that paroxetine can be used as a potent anticancer drug. Paroxetine, one of the selective serotonin reuptake inhibitors (SSRIs), has been widely prescribed for the treatment of depression and anxiety disorders. Recently, SSRIs have been reported to have anticancer activity in various types of cancer cells; however, the underlying mechanisms of their action are not yet known. In this study, we investigated the potential anticancer effect of paroxetine in human colorectal cancer cells, HCT116 and HT‐29. Treatment with paroxetine reduced cell viability, which was associated with marked increase in apoptosis, in both the cell lines. Also, paroxetine effectively inhibited colony formation and 3D spheroid formation. We speculated that the mode of action of paroxetine might be through the inhibition of two major receptor tyrosine kinases – MET and ERBB3 – leading to the suppression of AKT, ERK and p38 activation and induction of JNK and caspase‐3 pathways. Moreover, in vivo experiments revealed that treatment of athymic nude mice bearing HT‐29 cells with paroxetine remarkably suppressed tumour growth. In conclusion, paroxetine is a potential therapeutic option for patients with colorectal cancer.  相似文献   
74.
Carbonaceous materials are widely employed to host Li for stable and safe Li metal batteries while relatively little effort is devoted to tailoring the surface properties of carbon to facilitate uniform Li plating. Herein, the correlation between Li plating behavior and the surface characteristics of electrospun porous carbon nanofibers (PCNFs) is systemically elucidated through experiments and theoretical calculations. It is revealed that the neat carbon surface suffers from severe lattice mismatch with Li metal, hindering uniform Li plating. In contrast, open pores created on the PCNF surface serve as active sites for controlled initial nucleation of Li. The introduction of oxygenated functional groups further facilitates the nucleation of Li on PCNFs through the largely reduced nucleation energy barrier. The Li film uniformly deposited on PCNFs enables efficient use of the whole carbon surface, giving rise to enhanced cyclic stability of the electrode. When used as an anode in lithium–sulfur batteries, the modified electrode delivers an excellent energy density of 385 Wh kg?1 after 100 cycles. The fundamental correlation established in this study is universal to all types of carbonaceous materials and sheds new light on the rational design of high‐performance Li metal anodes by controlling the initial Li nucleation.  相似文献   
75.
Aqueous zinc ion batteries (AZIBs) are steadily gaining attention based on their attractive merits regarding cost and safety. However, there are many obstacles to overcome, especially in terms of finding suitable cathode materials and elucidating their reaction mechanisms. Here, a mixed‐valence vanadium oxide, V6O13, that functions as a stable cathode material in mildly acidic aqueous electrolytes is reported. Paired with a zinc metal anode, this material exhibits performance metrics of 360 mAh g?1 at 0.2 A g?1, 92% capacity retention after 2000 cycles, and 145 mAh g?1 at a current density of 24.0 A g?1. A combination of experiments and density functional theory calculations suggests that hydrated intercalation, where water molecules are cointercalated with Zn ions upon discharge, accounts for the aforementioned electrochemical performance. This intercalation mechanism facilitates Zn ion diffusion throughout the host lattice and electrode–electrolyte interface via electrostatic shielding and concurrent structural stabilization. Through a correlation of experimental data and theoretical calculations, the promise of utilizing hydrated intercalation as a means to achieve high‐performance AZIBs is demonstrated.  相似文献   
76.
Jung  Ye-Ha  Jang  Joon Hwan  Lee  Dasom  Choi  Yoobin  Choi  Soo-Hee  Kang  Do-Hyung 《Neurochemical research》2019,44(5):1192-1200

Catecholamines, including epinephrine (E), norepinephrine (NE), and dopamine (DA), are associated with the response to stressful conditions. However, the relationships of catecholamines with intelligence and their interactions with stress remain unclear. This study assessed stress, intelligence quotient (IQ), and catecholamine levels in 70 healthy subjects to elucidate associations between catecholamines and stress, and between catecholamines and IQ. Additionally, the associations of catecholamines with stress and IQ were analyzed according to hemispheric dominance using the Brain Preference Indicator (BPI). There were positive correlations between the NE/E ratio and the somatization of stress but negative correlations between the E/NE ratio and the somatization of stress among the total number of subjects. In the right-brain-dominant group, a high E/DA ratio was correlated with low levels of stress, somatization and depression, and high NE/E and DA/E ratios were associated with high levels of somatization. In the left-brain-dominant group, high E levels were correlated with low levels of depression. In the total subjects, there were positive correlations between the NE/E and DA/E ratios and the sum of the vocabulary, arithmetic, picture arrangement, and block design IQ subtests. Thus, these catecholamines were associated with stress and IQ, which suggests that the autonomic functional regulation of catecholamine levels in relation to stress may also affect cognitive functions related to intelligence in the brain. Furthermore, the relationships between catecholamines and stress or IQ differed depending on hemispheric dominance, which suggests that the present results could be used to inform the development of personalized therapies based on hemispheric asymmetry.

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77.
Males of the Mediterranean fruit fly, Ceratitis capitata, are strongly attracted to various plant odors, and previous work has demonstrated that male exposure to certain odors, including the scent of orange oil (OO) and ginger root oil (GRO), increases their mating success relative to non-exposed males. However, the mechanism(s) underlying this mating increase is not known. Here, we describe several experiments that further investigate the association between GRO- and OO-exposure and male signaling activity, pheromone attractiveness, and mating success in male medflies. Exposure to GRO or OO increased time spent pheromone calling but did not accelerate the rate of male sexual maturation. Using a wind tunnel, we compared female attraction to the pheromone of control, non-exposed males versus males previously exposed to OO or GRO. There was no evidence that GRO exposure enhanced the attractiveness of the male pheromone. The data for OO were inconclusive: females tended to spend more time on spheres emanating pheromone from OO-exposed males than on spheres emanating pheromone from non-exposed males, but the number of female landings did not differ between the two types of pheromone sources. Female choice tests confirmed that GRO- and OO-exposure boost male mating success relative to non-exposed males. Application of GRO directly to the abdomen reduced male mating success, whereas similar application of OO boosted male mating success. The potential role and mode of action of plant chemicals in the mating behavior of male medflies are evaluated in light of these findings.  相似文献   
78.
To determine the effectiveness of rehabilitation on improving ecosystem functions, we examined net photosynthetic rate (P N), tree species composition, soil enzyme activities, and the microclimate (air and soil temperature, relative humidity) of an area on Mt. Makiling that has been rehabilitated and protected from fire for over 12 years. After it was last burned extensively in 1991, restoration was initiated by planting Acacia mangium and Acacia auriculiformis. We selected three areas to study in 2003. Two areas were rehabilitated with A. mangium and A. auriculiformis, and one was still dominated by Imperata cylindrica and Saccharum spontaneum. P N of A. mangium and A. auriculiformis showed significantly lower values than those of I. cylindrica and S. spontaneum. The Acacia plantations had more naturally regenerated tree species than the grassland. Additionally, more tree species appeared in the A. mangium plantation than in the A. auriculiformis plantation. Ficus spetica was present in all of the study sites. Dehydrogenase and phosphatase activities were significantly higher in soil under the Acacia plantations than under grassland. Grassland showed higher air temperature, relative humidity, and soil temperature as well as a larger variation per hour in these parameters compared to the Acacia plantations. The highest air temperature, relative humidity, and soil temperature were measured in April during the dry season. From the regression analysis, soil temperature was significantly correlated with air temperature. Hence plantations, as a rehabilitation activity for grassland, promote natural regeneration and stabilize the microclimate. This stabilization of the microclimate affects establishment and growth of naturally occurring tree species.  相似文献   
79.

A white-colony-forming, facultative anaerobic, motile and Gram-stain-negative bacterium, designated G-1-2-2 T was isolated from soil of agriculture field near Kyonggi University, Republic of Korea. Strain G-1-2-2 T synthesized the polyhydroxybutyrate and could grow at 10–35 °C. The phylogenetic analysis based on 16S rRNA gene sequence showed that, strain G-1-2-2 T formed a lineage within the family Comamonadaceae and clustered as a member of the genus Ramlibacter. The 16S rRNA gene sequence of strain G-1-2-2 T showed high sequence similarities with Ramlibacter ginsenosidimutans BXN5-27 T (97.9%), Ramlibacter monticola G-3-2 T (97.9%) and Ramlibacter alkalitolerans CJ661T (97.5%). The sole respiratory quinone was ubiquinone-8 (Q-8). The major polar lipids were phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, and an unidentified phospholipid. The principal cellular fatty acids were C16:0, cyclo-C17:0, summed feature 3 (C16:1ω7c and/or C16:1ω6c) and summed feature 8 (C18:1ω7c and/or C18:1ω6c). The genome of strain G-1-2-2 T was 7,200,642 bp long with 13 contigs, 6,647 protein-coding genes, and DNA G?+?C content of 68.9%. The average nucleotide identity and in silico DNA–DNA hybridization values between strain G-1-2-2 T and close members were?≤?81.2 and 24.1%, respectively. The genome of strain G-1-2-2 T showed eight putative biosynthetic gene clusters responsible for various secondary metabolites. Genome mining revealed the presence of atoB, atoB2, phaS, phbB, phbC, and bhbD genes in the genome which are responsible for polyhydroxybutyrate biosynthesis. Based on these data, strain G-1-2-2 T represents a novel species in the genus Ramlibacter, for which the name Ramlibacter agri sp. nov. is proposed. The type strain is G-1-2-2 T (=?KACC 21616 T?=?NBRC 114389 T).

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80.
The soybean pod borer, Maruca vitrata is one of the key insect pests of tropical legumes. It damages tender leaf axils, flower buds, flowers and pods by webbing and boring clusters of flowers and pods. In this study, we investigated the survival and life table parameters of M. vitrata on several leguminous crops; soybean (cvs. Daewon, Poongsannamool and Socheongja), azuki bean (cv. Hongeon), mung bean (cv. Sanpo), and cowpea (cv. Jangchae), compared to artificial diet to assess the antibiosis resistance to M. vitrata. The life‐variables of M. vitrata were significantly affected by the tested legume cultivars. None of the larvae fed cowpea cultivar Jangchae survived. The azuki bean cultivar Hongeon and mung bean cultivar Sanpo were found susceptible to M. vitrata, whereas cowpea cultivar Jangchae and soybean cultivar Daewon showed antibiosis resistance to M. vitrata. Further studies should examine the chemicals associated with leguminous crop cultivars and its mechanism to develop a control method against M. vitrata.  相似文献   
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