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A fully conjugated figure‐of‐eight nanohoop is presented with facile synthesis. The molecule's lemniscular skeleton features the combination of two strained oligoparaphenylene loops and a flexible cyclooctatetrathiophene core. Its rigid yet guest‐adaptive cavities enable the formation of the peanut‐like 1:2 host–guest complexes with C60 or C70, which have been confirmed by X‐ray crystallography and characterized in solution. Further computational studies suggest notable geometric variations and non‐covalent interactions of the cavities upon binding with different fullerenes, as well as overall conjugation comparable to cycloparaphenylenes. [ABSTRACT FROM AUTHOR]

A fully conjugated figure‐of‐eight nanohoop is presented with facile synthesis. The molecule's lemniscular skeleton features the combination of two strained oligoparaphenylene loops and a flexible cyclooctatetrathiophene core. Its rigid yet guest‐adaptive cavities enable the formation of the peanut‐like 1:2 host–guest complexes with C60 or C70, which have been confirmed by X‐ray crystallography and characterized in solution. Further computational studies suggest notable geometric variations and non‐covalent interactions of the cavities upon binding with different fullerenes, as well as overall conjugation comparable to cycloparaphenylenes. [ABSTRACT FROM AUTHOR]

[Display omitted] • A method to detect the Ca2+ fluorescence intensity by integrating μLED linear array and optical fiber with depth resolution is proposed. • The excitation range of each μLED in the μLED linear array can't overlap with each other by controlling the luminous intensity. • When the μLED linear array turns on alternately, the excitation light has depth resolution. • Fluorescence at different location can be collected by an optical fiber. • Processing the fluorescence signals by the time-division multiplexing method, the fluorescence signals at a different location can be obtained. Calcium (Ca2+) fluorescence is widely used to monitor the activity of neurons in vivo. We propose a method of detection the Ca2+ fluorescence intensity by integrating a μLED linear array and an optical fiber. Due to the different positions of each μLED, the range of excitation of each μLED cannot overlap that of another by controlling the luminous intensity. When each μLED in a linear array is switched on in turn, only one μLED is emitting at any given time. In this way, the fluorescence from the active neurons collected by a single fiber can correspond to the position of the μLED according to the time sequence of each μLED, thus resulting in the relative position of the recorded fluorescence being distinguished. When the scanning speed of a μLED is much higher than the fluorescence process associated with Ca2+ activity, the device can simultaneously obtain the Ca2+fluorescence activity signals from multiple sites, thus inferring the activity of neurons through the fluorescence intensity, so that the neuron activity with depth resolution can be obtained. In the present work, the prototype device and system are constructed, and the method has been verified by simulation in vitro and green fluorescent protein (GFP) in vivo. [ABSTRACT FROM AUTHOR]

Cotton has a complex branching pattern including sympodial and vegetative branching. Traditionally managed cotton mainly depends on sympodial branching for formation of yield-contributing fruit. Whether seedcotton yield based solely on vegetative branching is comparable with that based solely on sympodial or both types of branching is unclear. The study determined how terminal removal at first square to avoid formation of sympodial branches (SBs) regulated vegetative branching and yield under different plant densities. A two-year split-plot design field experiment had main plots with plant density (4.5 and 9.0 plants m−2) and subplots with plant pruning mode. Pruning modes were terminal removal at first square (TRS) to avoid formation of sympodial branches but retain only vegetative branches (VBs), removal of VBs (RVB) to retain only SBs, and no pruning (CK), with both branch types remaining intact. Canopy photosynthesis, dry matter accumulation and partitioning, and seedcotton yield and yield components were examined. At low plant density (4.5 plants m−2), compared with other pruning modes, TRS increased seedcotton yield and biological yield but did not affect harvest index. At high plant density (9.0 plants m−2), compared with other pruning modes, TRS decreased seedcotton yield and harvest index, although biological yield increased. The yield increase with TRS at low plant density was attributed to the increase in biological yield, which was due to significantly higher canopy photosynthesis with TRS than with other pruning modes. At high plant density, photosynthesis with TRS was higher than that with no pruning at peak boll-setting and boll-opening stages and higher than that with RVB from peak squaring to boll-opening. Compared with other pruning modes, TRS increased dry matter partitioning to vegetative organs but decreased partitioning to reproductive organs. Pearson correlation analysis revealed a significant positive correlation between canopy apparent photosynthesis and biological yield, biomass partitioning, and harvest index, irrespective of plant pruning and plant density. Plant pruning and plant density interacted to affect seedcotton yield. With TRS, cotton yield at low plant density was higher than that with other pruning modes, which was attributed to an increase in biological yield associated with an increase in canopy photosynthesis. At high plant density, the yield decrease with TRS was attributed to low harvest index associated with reduced reproductive partitioning. Cotton cultivation relying solely on vegetative branching can be an alternative to obtain moderate yields and economic benefits under conditions of low plant density. • Plant pruning and density affected cotton branching and yield formation. • Terminal removal at first square led to the highest seed cotton yield at low plant density. • Terminal removal at first square increased yield by promoting canopy photosynthesis. [ABSTRACT FROM AUTHOR]

Root system architecture (RSA) plays an important role in soil water uptake and plant growth. However, there is a lack of understanding regarding the connection between the changes in RSA characteristics under drought stress in cotton plants and their drought tolerance and yield. This study aims to evaluate the RSA variations in different drought-tolerant cotton cultivars under drought stress, and to assess the correlation between RSA, drought tolerance, and yield. Three drought-tolerant cotton cultivars and three drought-sensitive cotton cultivars were grown in a field equipped with rain shelters to prevent interference from rainfall. Drought stress was initiated at the three-leaf stage, maintaining the soil relative water content at 50 ± 5%, while control plants were irrigated normally at 75 ± 5% soil water content. Multiple parameters, including leaf water potential, relative water content, seed cotton yield, and RSA traits, were assessed. Notable variations in drought tolerance were observed among different cultivars when exposed to drought stress. Specifically, drought-tolerant cultivars exhibited a 34% increase in the average length of all lateral roots and a 15% increase in maximum root depth under drought stress. In contrast, seed cotton yield experienced a reduction of 22.34% in such conditions. Interestingly, there were significant differences in several RSA traits under drought stress, which were not evident under well-watered. Leaf water potential and relative water content were positively correlated with specific root length, dry root weight, average length of all lateral roots and maximum depth, and negatively correlated with average lateral root emergence angle and width/depth ratio. These results underscore the close association between RSA traits and plant drought tolerance. There was also a strong correlation between the seed cotton yield and RSA traits. Specifically, seed cotton yield increased linearly with specific root length, average lengths of lateral roots, and maximum depth, but decreased linearly with root tissue density, and average lateral root emergence angle and width/depth ratio. Optimizing RSA improves drought tolerance and reduces yield loss in drought-tolerant cotton cultivars. Understanding of the role of RSA in plant adaptation to drought stress is important for selecting and developing high-yielding cultivars with superior drought tolerance. This knowledge holds great significance in improving cotton resilience and facilitating adapting to abiotic stress through genetic improvement or agronomic measures. • Genotypic variation in root system architecture (RSA) was revealed under drought. • Root system architecture plays important roles in cotton drought tolerance. • There is a significant coefficient of variation in RSA under drought. • Optimizing RSA can improve cotton drought tolerance and minimize yield loss under drought.. [ABSTRACT FROM AUTHOR]

Abstract: A family of thieno[3,2-b]pyridine based small molecule inhibitors of c-Met and VEGFR2 were designed based on lead structure 2. These compounds were shown to have IC50 values in the low nanomolar range in vitro and were efficacious in human tumor xenograft models in mice in vivo. [Copyright &y& Elsevier]

Alloys, especially Mo–Ni alloys, are excellent HER electrocatalysts in alkaline solution. The HER activity of the Mo–Ni alloys can be improved by grafting H2O dissociation promoters (metal oxides or hydroxides) to promote the dissociation of H2O in alkaline solution. However, most of the reported Mo–Ni alloys grafting with H2O dissociation promoters only have simple one-dimensional (1D) structures, which cannot further improve the catalytic performance. Compared with 1D nanomaterials, two-dimensional (2D) nanomaterials have higher specific surface area, electrical conductivity, more exposed active sites and mass transfer channels. Herein, a novel 2D nanosheets self-supporting composite electrocatalyst MoNi4/MoO2.5-NF derived from the NiMoO4 nanosheets was reported for the first time. Benefiting from the unique 2D nanosheets structure and the synergistic effect of each component, the catalyst shows high electrocatalytic HER activity in 1 M KOH solution. The MoNi4/MoO2.5-NF needs overpotential of 49 mV to reach 10 mA cm−2. The HER activity of MoNi4/MoO2.5-NF can be further improved through electrochemical-cycling activation (CV) process. After 10 CV cycles, the overpotential to reach 10 mA cm−2 of the catalyst decreased from 49 to 27 mV and even exceeded 20% Pt/C (32 mV). The improvement of HER performance is attributed to the increase in the electrochemically active surface area, the reduced impedance and Tafel slope after CV process. [ABSTRACT FROM AUTHOR]

Waterlogging stress is an increasing threat to cotton production worldwide. The use of cultivation measures to combat waterlogging stress is a promising approach. As a traditional cultural practice, ridge intertillage is usually conducted before flowering to form a ridge along a row and a furrow between two rows in order to reduce lodging and control weeds in cotton fields. However, it is unclear whether ridge intertillage can alleviate waterlogging stress in field-grown cotton. Flat and ridge intertillage were conducted at 10 days after squaring of cotton to establish flat and ridge–furrow configurations, respectively, with or without 10-d waterlogging. To determine effects of intertillage pattern on mitigating waterlogging stress, changes in rhizosphere bacterial communities and plant physiological parameters were examined in waterlogged cotton. Compared with flat tillage, ridge intertillage significantly decreased hydrogen peroxide production, malonaldehyde content, and alcohol dehydrogenase and pyruvate decarboxylase activities in both roots and leaves of waterlogged cotton but significantly increased nitrogen, phosphorus, and potassium concentrations, leaf area, and plant biomass. Compared with flat intertillage under waterlogging (FIW), ridge intertillage under waterlogging (RIW) changed the abundance and composition of rhizosphere bacterial communities. In addition, several taxa of bacteria with beneficial functions were enriched in the rhizosphere under ridge intertillage. Pearson correlations indicated that changes in rhizosphere bacteria and plant physiological parameters in waterlogged cotton were significantly correlated (P < 0.05), suggesting that adjustments in rhizosphere bacterial communities were involved in the physiological response to waterlogging stress. Moreover, compared with FIW, RIW increased canopy photosynthesis and lint yield of waterlogged cotton by 51.5% and 18.3%, respectively, and decreased lint yield loss by 61.3%. Compared with flat intertillage, ridge intertillage induced adjustments in rhizosphere bacterial communities, reduced oxidative membrane damage, improved nutrient uptake and canopy photosynthesis, and ultimately reduced the stress damage and yield loss of waterlogged cotton. Ridge intertillage before flowering is a promising agronomic measure to combat waterlogging stress in cotton and possibly other major field crops. • Ridge intertillage produced ridge-furrow configuration by piling up the topsoil to cotton plants base before flowering. • Effects of flat and ridge intertillage on waterlogged cotton were compared. • Ridge intertillage adjusted rhizosphere microbe and nutrient uptake of waterlogged cotton. • The adjustments induced a set of physiological changes and reduced the yield loss of waterlogged cotton. [ABSTRACT FROM AUTHOR]

Basal and topdressing split application of nitrogen (N) fertilizer is widely used in cotton in many cotton-growing countries, including China. Recently, in the Yellow River valley of China, one-off basal application of N fertilizer has been applied to meet the challenge of increasing labor costs. However, how one-off basal application of N fertilizer affects cotton yields and N use efficiency and by what mechanisms are not clear. Therefore, an experiment was conducted using full-season (K836) and short-season (LM532) cotton cultivars in a moderate fertility field in the Yellow River valley in 2019 and 2020. A split-plot design was established for each variety with the main plots assigned to a mulching pattern (with or without plastic film mulching) and the subplots assigned to an N rate (0 or 195 kg N ha−1, abbreviated as N0 and N195). Cotton yield and yield components, biomass accumulation and distribution, and total N and 15N absorption and utilization were determined each year. Compared with N0, one-off basal application of N fertilizer (N195) did not increase boll density, boll weight, lint percentage or seedcotton yield regardless of cultivar or mulching. Biomass and total N uptake of cotton increased significantly in N195 compared with N0, but the increases occurred primarily in vegetative organs, leading to reductions in the harvest index and N yield efficiency index. With one-off basal application of N fertilizer, more than 80 % of the N in cotton plants derived from soil. Approximately 28 % of 15N-labeled urea was absorbed by cotton plants, of which only approximately 35 % was used in forming seedcotton yield. Therefore, cotton plants with one-off basal application of N fertilizer only recovered a small amount of fertilizer N, and even less of the fertilizer N was used in yield formation. As a result, the harvest index of cotton decreased, and thus, one-off basal application of N fertilizer failed to increase seedcotton yield. Cultivar and plastic film mulching did not alter the effects of one-off basal application of N fertilizer. Therefore, although one-off basal application of N fertilizer in cotton is a labor-saving approach, it should not be encouraged in moderate fertility soil in the Yellow River valley or other areas with similar ecology. • One-off basal N application did not increase the seedcotton yield compared with no-N fertilization. • One-off N application led to a low proportion of plant N derived from 15N and even less for yield formation. • Both N uptake and N distribution to vegetative organs was improved by one-off basal N application. • Cultivar and plastic mulching did not alter the effects of one-off basal application of N fertilizer. [ABSTRACT FROM AUTHOR]

Manual removal of the main-stem growth tip is traditionally used to break the apical dominance of cotton (Gossypium hirsutum L.). Chemical topping with plant growth regulators also effectively inhibits apical dominance. However, the effect of chemical topping on yield increases and whether plant density or ecological conditions affect its efficacy are unclear. Therefore, a three-year field experiment with a split-plot design was conducted to determine the effects of plant topping, plant density, and their interactions on cotton yield and related physiological and agronomical parameters at three sites with different ecological conditions in China. In each site, the main plots were assigned low, moderate, or high plant density and the subplots were assigned no topping, manual topping, or chemical topping. Growth, yield, yield components, earliness, and late-season leaf photosynthesis as well as labor and material inputs were examined each year. Compared with no topping, both chemical and manual topping greatly reduced plant height at all sites. Manual topping increased seed cotton yield and earliness in all tested plant densities and sites. However, plant density but not ecological condition greatly mediated the effect of chemical topping on yield. At low plant density, the yields with chemical topping were 4–6% lower than those with no topping and 5.5–10.8% lower than those with manual topping at the three sites. Although yields with chemical topping were comparable with those of manual topping at moderate and high plant densities, they were 8.6–12.8% higher at moderate density and 13.8–16.4% higher at high plant density than those with no topping across years and sites. Averaged across the sites, chemical topping reduced biological yield by 12.7% at low plant density. Although biological yield decreased slightly, chemical and manual topping increased the harvest index by 12.4% and 13.3% at moderate density and by 15.6% and 17.4% at high density, respectively. In comparison with no topping, the reduction in seed cotton yield with chemical topping at low plant density was attributed to insufficient biological yield, whereas the increase in yield at moderate and high plant densities was mainly due to greater partitioning of assimilates to reproductive tissues. Compared with manual topping, chemical topping produced 23.2% lower net returns as a result of lower seed cotton yield at low plant density but produced 8.1% and 20.9% higher net returns at moderate and high plant densities, respectively, because of savings in labor inputs and comparable seed cotton yields. In addition, chemical topping increased the earliness percentage compared with that of no topping. Overall, this study demonstrates that chemical topping is a promising alternative to traditional manual topping under moderate or high cotton plant density. • Manual topping increased cotton yield regardless of plant densities and ecological conditions relative to non-topping. • Chemical topping decreased yield at low plant density relative to non-topping because of greater biomass reduction. • Chemical topping increased cotton yield at moderate and high plant densities via greater assimilates partitioning to fruits. • Chemical topping could replace manual topping at moderate and high plant densities without ecological dependence. [ABSTRACT FROM AUTHOR]

Abstract: A series of N-(4-(6,7-disubstituted-quinolin-4-yloxy)-3-fluorophenyl)-2-oxo-3-phenylimidazolidine-1-carboxamides targeting c-Met and VEGFR2 tyrosine kinases was designed and synthesized. The compounds were potent against these two enzymes with IC50 values in the low nanomolar range in vitro, possessed favorable pharmacokinetic profiles and showed high efficacy in vivo in several human tumor xenograft models in mice. [Copyright &y& Elsevier]

Abstract: Potent SAH analogues with constrained homocysteine units have been designed and synthesized as inhibitors of human DNMT enzymes. The five membered (2S,4S)-4-mercaptopyrrolidine-2-carboxylic acid, in 1a, was a good replacement for homocysteine, while the corresponding six-member counterpart was less active. Further optimization of 1a, changed the selectivity profile of these inhibitors. A Chloro substituent at the 2-position of 1a, compound 1d, retained potency against DNMT1, while N6 alkylation, compound 7a, conserved DNMT3b2 activity. The concomitant substitutions of 1a at both 2- and N6 positions reduced activity against both enzymes. [Copyright &y& Elsevier]

Abstract: The inhibitory activity of base-modified SAH analogues and the specificity of inhibiting human DNMT1 and DNMT3b2 enzymes was explored. The 6-amino group was essential while the 7-N of the adenine ring of SAH could be replaced by CH– without loss of activity against both enzymes. The introduction of small groups at the 2-position of the adenine moiety favors DNMT1 over DNMT3b2 inhibition whereas alkylation of the N 6-amino moiety favors the inhibition of DNMT3b2 enzyme. [Copyright &y& Elsevier]

Abstract: A series of N-(3-fluoro-4-(2-arylthieno[3,2-b]pyridin-7-yloxy)phenyl)-2-oxo-3-phenylimidazolidine-1-carboxamides targeting c-Met and VEGFR2 tyrosine kinases was designed and synthesized. The compounds were potent against these two enzymes with IC50 values in the low nanomolar range in vitro, possessed favorable pharmacokinetic profiles and showed high efficacy in vivo in several human tumor xenograft models in mice. [Copyright &y& Elsevier]

Abstract: A series of thieno[3,2-b]pyridine-based inhibitors of c-Met and VEGFR2 tyrosine kinases is described. The compounds demonstrated potency with IC50 values in the low nanomolar range in vitro while the lead compound also showed in vivo activity against various human tumor xenograft models in mice. Further exploration of this class of compounds is underway. [Copyright &y& Elsevier]