G × E × M analysis to define allometric rules between leaves and stems in wheat.

Allometric rules provide insights into the structure-function relationships across species and scales and are commonly used in ecology. The fields of agronomy, plant phenotyping and modeling also need simplifications such as allometric rules to reconcile data at different temporal and spatial levels (organs/canopy). This paper explores the variations in relationships for wheat regarding (i) the distribution of crop green area between leaves and stems, and (ii) the allocation of above-ground biomass between leaves and stems during the vegetative period, using a large dataset covering different years, countries, genotypes and management practices. Our results show that the relationship between leaf and stem area was linear, genotype-specific, and sensitive to radiation. The relationship between leaf and stem biomass depended on genotype and nitrogen fertilization. The mass per area, associating area and biomass for both leaf and stem, varied strongly by developmental stage and was significantly affected by environment and genotype. These allometric rules were evaluated with satisfactory performance, and their potential use is discussed with regard to current phenotyping techniques and plant/crop models. Our results enable the definition of models and minimum datasets required for characterizing diversity panels and making predictions in various G × E × M contexts.

Effect of blood flow-restrictive resistance training on metabolic disorder and body composition in older adults with type 2 diabetes: a randomized controlled study.

Introduction: To explore whether blood flow-restrictive resistance exercise (BFRE) can be used as an alternative strategy to moderate-intensity resistance training (RT) to improve metabolic disorder and body composition in older adults with type 2 diabetes (T2DM). Methods: This is a single-blind, randomized, controlled trial. Ninety-eight older adults with T2DM were randomly divided into three groups: BFRE group (n = 34), RT group (n = 31) and control group (n = 33). Two exercise groups received supervised collective training for a period of six months, each lasting 50 min, three times a week. The primary outcomes included fasting plasma glucose (FPG), Glycosylated hemoglobin (HbA1c), blood lipids, blood pressure, and body composition. The secondary outcome was muscle performance. Results: After six months of intervention, the FPG, HbA1c, blood lipids, diastolic blood pressure, body composition, and muscle performance of the two exercise groups were significantly improved relative to the control group and baseline measurements (P < 0.05). There was no significant increase in lean mass between the two exercise groups compared to the control group and baseline (p > 0.05). There was no significant decrease in systolic blood pressure between the two exercise groups compared to the control group (p > 0.05), but it was significantly lower than their baseline (P < 0.05). There was no significant difference in all indicators between the two exercise groups at the baseline, third and sixth months of intervention (p > 0.05). Discussion: BFRE can safely and effectively improve the metabolic disorder and body composition of older adults with T2DM. For elderly exercise beginners, BFRE can be used as an alternative strategy to moderate-intensity resistance training. Clinical trial registration: https://www.chictr.org.cn/showproj.html?proj=178886, identifier ChiCTR2300074357.

Comparing the Developmental Toxicity Delay and Neurotoxicity of Benzothiazole and Its Derivatives (BTHs) in Juvenile Zebrafish.

In this study, a semi-static water exposure method was employed to investigate the early developmental and neurotoxic effects of four benzothiazole substances (BTHs), namely benzothiazole (BTH), 2-mercaptobenzothiazole (MBT), 2-hydroxybenzothiazole (BTON), and 2-aminobenzothiazole (2-ABTH), on zebrafish at an equimolar concentration of 10 µM. The findings revealed that all four BTHs exerted certain impacts on early development in zebrafish. MBT stimulated spontaneous movement in juvenile zebrafish, whereas BTON inhibited such movements. Moreover, all four BTHs hindered the hatching process of zebrafish larvae, with MBT exhibiting the strongest inhibition at 24 h post-fertilization (hpf). Notably, MBT acted as a melanin inhibitor by suppressing melanin production in juvenile zebrafish eyes and weakening phototaxis. Additionally, both BTH and BTON exhibited significantly lower speeds than the control group and other test groups under conditions without bright field stimulation; however, their speeds increased to average levels after percussion stimulation, indicating no significant alteration in motor ability among experimental zebrafish groups. Short-term exposure to these four types of BTHs induced oxidative damage in zebrafish larvae; specifically, BTH-, MBT-, and BTON-exposed groups displayed abnormal expression patterns of genes related to oxidative damage. Exposure to both BTH and MBT led to reduced fluorescence intensity in transgenic zebrafish labeled with central nervous system markers, suggesting inhibition of central nervous system development. Furthermore, real-time quantitative PCR results demonstrated abnormal gene expression associated with neural development. However, no significant changes were observed in 2-ABTH gene expression at this concentration. Overall findings indicate that short-term exposure to BTHs stimulates neurodevelopmental gene expression accompanied by oxidative damage.

Highly dispersed palladium nano-catalyst anchored on N-doped nanoporous carbon microspheres derived from chitosan for efficient and stable hydrogenation of quinoline.

Under the background of green chemistry, the synthesis of N-heterocycles using efficient, stable and long-life catalysts has still faced great challenges. Herein, we used biomass resource chitosan to fabricate a nanoporous chitosan carbon microsphere (CCM), and successfully designed a stable and efficient Pd nano-catalyst (CCM/Pd). Various physicochemical characterizations provided convincible evidences that the palladium nanoparticles (NPs) were tightly and evenly dispersed on the CCM with a mean diameter of 2.28 nm based on the nanoporous structure and abundant functional N/O groups in CCM. Importantly, the graphitized constructure, the formed defects and larger surface area in CCM were able to promote the immobilization of Pd NPs and the electron transfer between Pd and CCM, thereby significantly improving the catalytic activity. The CCM/Pd catalyst was applied for hydrogenation of quinoline compounds, which showed excellent catalytic activity and durability, as well as good substrate applicability. The application of renewable biomass-based catalysts contributes to the progression of a green/sustainable society.

The pattern of abandoned cropland and its productivity potential in China: A four-years continuous study.

The increased requirement of food production with the rising population challenges limited cultivation land in China. The abandoned cropland has high potential in grain production to ensure China's food security. However, the spatial distributions of abandoned cropland in China are understudied and therefore it is difficult to estimate its potential grain production. Our study proposed a new definition of abandoned cropland considering unique multiple cropping systems in China, and estimate the abandoned cropland distribution and grain productivity potential by using Landsat-8 and GF-1 images under deep learning technology. The area of abandoned cropland in three main grain-producing regions was approximately 1.53 million hectares during 2014-2017. The estimated images agreed with the field survey and the national agricultural statistical data with the accuracy larger than 87 %. The spatial distribution of abandoned cropland in China was scattered and a high abandonment rate observed in the Middle-lower Yangtze River Plain. Moreover, the uncultivated cropland accounted for approximately 50 % of the total area of abandoned cropland. The maximum production potential of abandoned cropland could reach 8.5 million tons, including 2.7, 2.5 and 3.3 million tons of maize, wheat and rice, respectively. The exploitation of abandoned cropland is also beneficial for additional soybean production in China. National-scale estimation of abandoned cropland in China is crucial for land use policy making and cropland protection, as well the implementation of national food security strategy.

Silver lining to a climate crisis in multiple prospects for alleviating crop waterlogging under future climates.

Extreme weather events threaten food security, yet global assessments of impacts caused by crop waterlogging are rare. Here we first develop a paradigm that distils common stress patterns across environments, genotypes and climate horizons. Second, we embed improved process-based understanding into a farming systems model to discern changes in global crop waterlogging under future climates. Third, we develop avenues for adapting cropping systems to waterlogging contextualised by environment. We find that yield penalties caused by waterlogging increase from 3-11% historically to 10-20% by 2080, with penalties reflecting a trade-off between the duration of waterlogging and the timing of waterlogging relative to crop stage. We document greater potential for waterlogging-tolerant genotypes in environments with longer temperate growing seasons (e.g., UK, France, Russia, China), compared with environments with higher annualised ratios of evapotranspiration to precipitation (e.g., Australia). Under future climates, altering sowing time and adoption of waterlogging-tolerant genotypes reduces yield penalties by 18%, while earlier sowing of winter genotypes alleviates waterlogging by 8%. We highlight the serendipitous outcome wherein waterlogging stress patterns under present conditions are likely to be similar to those in the future, suggesting that adaptations for future climates could be designed using stress patterns realised today.

The toxic effect of bisphenol AF and nanoplastic coexposure in parental and offspring generation zebrafish.

Microplastics (MPs) and bisphenol AF (BPAF) are two environmental pollutants that usually coexist in the natural environment. Studies of MPs or BPAF have gradually increased in recent years, but few studies have focused on the combination toxic effects. In this study, the subchronic model of adult zebrafish was exposed to 1 mg/L nanolevel microplastics and 200 µg/L BPAF for 45 days; the parental zebrafish were spawning every 3 days during exposure, and the effects of continuous poisoning were examined on the offspring after 1-9 spawns. The results showed that single BPAF exposure or BPAF and nanoplastic coexposure can both decrease the number of eggs laid and the locomotor behavior of parental zebrafish and impact the hatching rate, mortality, body length and locomotor behavior of offspring zebrafish, especially in 7-9 spawn. BPAF were accumulated in parental zebrafish intestinal in 334.62 ng/g in BPAF group and 594.52 ng/g in nm+BPAF group, and accumulated in whole offspring zebrafish for 281.6 ng/g in BPAF group and 321.46 ng/g in nm+BPAF group. Neurodevelopmental, inflammation, apoptosis and oxidative stress-related genes were also significantly increased after 7-9 spawn. In addition, the exacerbated accumulation in the BPAF+nm group in parental and offspring zebrafish may be the reason for the accelerated toxic effect in the present research. In this study, we investigated the combined effects of nanoplastics and BPAF on parental and offspring zebrafish in the aquatic environment to identify the accumulative toxic effects and provide new experimental support for assessing the effects of coexposure on aquatic organisms.

Whole farm planning raises profit despite burgeoning climate crisis.

The climate crisis challenges farmer livelihoods as increasingly frequent extreme weather events impact the quantum and consistency of crop production. Here, we develop a novel paradigm to raise whole farm profit by optimising manifold variables that drive the profitability of irrigated grain farms. We build then invoke a new decision support tool-WaterCan Profit-to optimise crop type and areas that collectively maximise farm profit. We showcase four regions across a climate gradient in the Australian cropping zone. The principles developed can be applied to cropping regions or production systems anywhere in the world. We show that the number of profitable crop types fell from 35 to 10 under future climates, reflecting the interplay between commodity price, yield, crop water requirements and variable costs. Effects of climate change on profit were not related to long-term rainfall, with future climates depressing profit by 11-23% relative to historical climates. Impacts of future climates were closely related to crop type and maturity duration; indeed, many crop types that were traditionally profitable under historical climates were no longer profitable in future. We demonstrate that strategic whole farm planning of crop types and areas can yield significant economic benefits. We suggest that future work on drought adaptation consider genetic selection criteria more diverse than phenology and yield alone. Crop types with (1) higher value per unit grain weight, (2) lower water requirements and (3) higher water-use efficiency are more likely to ensure the sustainability and prosperity of irrigated grain production systems under future climates.

Long-term exposure of zebrafish to bisphenol F: Adverse effects on parental reproduction and offspring neurodevelopment.

Bisphenol F (BPF), an alternative to bisphenol A (BPA) has potential endocrine and reproductive toxicity; however, the effects of environmental concentrations of BPF on the reproductive and developmental toxicity of offspring following parental exposure to BPF remain unclear. In the present study, the effects of life-cycle BPF exposure at environmental concentrations on zebrafish reproduction, offspring growth, and development were investigated. The results showed that the life-cycle of BPF exposure significantly elevated oxidative stress levels, increased gonadal apoptosis, and reduced zebrafish (F0) spawning. Notably, through maternal transfer, BPF exposure significantly affected offspring development. Developmental parameters such as hatching rate, spontaneous movements, heart rate, body length, and locomotor behavior decreased in zebrafish larvae (F1). In addition, the expression levels of genes related to oxidative stress, apoptosis, and neurodevelopment were altered in F1 larvae. Therefore, the present study provides evidence that BPF, even at environmental concentrations, can be potentially adverse in terms of reproductive defects and offspring neurodevelopmental disorders. Therefore, BPF, as a substitute for BPA, is worthy of in-depth evaluation.

The potential mechanism of BPF-induced neurotoxicity in adult zebrafish: Correlation between untargeted metabolomics and gut microbiota.

Bisphenol F (BPF) is becoming the main substitute for bisphenol A (BPA) in plastics for food and beverage applications. Previous studies have demonstrated the neurotoxicity of BPF; however, its lifecycle toxicity and the underlying mechanisms remain poorly understood. In the current study, zebrafish were continuously exposed to BPF for four months from the embryo to adult stages in order to assess its neurotoxicity. Locomotor behaviors significantly decreased after BPF exposure, which was accompanied by a decrease in body weight, length, and hatching rate. Additionally, BPF increased the expression of inflammatory genes in the brain and destroyed the zebrafishes' intestinal integrity. Meanwhile, the 16S rRNA gene sequence results showed a significantly decreased microbiota abundance and diversity following BPF treatment. Neurotransmitter metabolites were also altered by BPF. Notably, the correlation analysis between microbiota and neurotransmitter metabolism verified that gut microbiota dysbiosis was closely related to the disturbance of neurotransmitter metabolites. Therefore, the present study evaluated the neurotoxicity of lifecycle exposure to BPF and unraveled a novel mechanism involving disturbance of neurotransmitter metabolism and gut dysbiosis, which may provide potential targets for BPF-mediated neurotoxicity.

Facile fabrication of highly dispersed Pd catalyst on nanoporous chitosan and its application in environmental catalysis.

With the development of society, the problem of environmental pollution is becoming increasingly serious, such as the typical pollution of nitro compounds or dyes in wastewater. An effective strategy to remove these organic pollutants is catalytic conversion, including converting them into more chemically valuable compounds. Herein, a nanoporous chitosan microsphere derived from seafood waste resources of chitin was constructed via sol-gel method, which was used as supports to successfully fabricate a highly dispersed Pd nano-catalyst (mean diameter ~ 1.8 nm) via a facile way based on its interconnected nanoporous structure and rich functional -OH/-NH2 groups. The synthetic catalyst was applied to the hydrogenation of toxic nitro compounds, which could efficiently and selectively catalyze the conversion of nitro compounds. The catalyst was also used for the degradation of some representative dyes, which also showed good activity and stability, suggesting potential of applications in green environmental governance.

A systematic comparison of neurotoxicity of bisphenol A and its derivatives in zebrafish.

As more and more countries have prohibited the manufacture and sale of plastic products with bisphenol A (BPA), a number of bisphenol analogues (BPs), including BPS, BPF and BPAF, have gradually been used as its primary substitutes. Ideally, substitutes used to replace chemicals with environmental risks should be inert, so it makes sense that the risk of the similar chemical substitutes (BPS, BPF, and BPAF) should be assessed before they used. Therefore, in the present study, the neurotoxicity of four BPs at environmentally relevant concentration (200 µg/L) were systematically compared using zebrafish as a model. Our results showed that the four BPs (BPA, BPS, BPF and BPAF) exhibited no obvious effect on the hatchability, survival rate and body length of zebrafish larvae, noteworthily a significant inhibitory effect on spontaneous movement at 24 hpf was observed in the BPA, BPF and BPAF treatment groups. Behavioral tests showed that BPAF, BPF and BPA exposure significantly reduced the locomotor activity of the larvae. Additionally, BPAF treatment adversely affected motor neuron axon length in transgenic lines hb9-GFP zebrafish and decreased central nervous system (CNS) neurogenesis in transgenic lines HuC-GFP zebrafish. Intriguingly, BPAF displayed the strongest effects on the levels and metabolism of neurotransmitters, followed by BPF and BPA, while BPS showed the weakest effects on neurotransmitters. In conclusion, our study deciphered that environmentally relevant concentrations of BPs exposure exhibited differential degrees of neurotoxicity, which ranked as below: BPAF > BPF ≈ BPA > BPS. The possible mechanisms can be partially ascribed to the dramatical changes of multiple neurotransmitters and the inhibitory effects on neuronal development. These results suggest that BPAF and BPF should be carefully considered as alternatives to BPA.

Protective Effects of Lignin-Carbohydrate Complexes from Wheat Stalk against Bisphenol a Neurotoxicity in Zebrafish via Oxidative Stress.

Lignin-carbohydrate complexes (LCCs) from different lignocellulosic biomass have shown biological qualities as antioxidant and immunostimulant. By contrast, the application of LCCs as protectant against neurotoxicity caused by different compounds is scarce. In this work, two kinds of LCCs with carbohydrate-rich and lignin-rich fractions were obtained from wheat stalk and used to protect against BPA-neurotoxicity in zebrafish. The results showed that BPA at a concentration of 500 µg/L results in neurotoxicity, including significant behavioral inhibition, and prevents the expression of central nervous system proteins in transgenic zebrafish models (Tg (HuC-GFP)). When the zebrafish was treated by LCCs, the reactive oxygen species of zebrafish decreased significantly with the change of antioxidant enzymes and lipid peroxidation, which was due to the LCCs' ability to suppress the mRNA expression level of key genes related to nerves. This is essential in view of the neurotoxicity of BPA through oxidative stress. In addition, BPA exposure had negative effects on the exercise behavior, the catalase (CAT) and superoxide dismutase (SOD) activity, and the larval development and gene expression of zebrafish larvae, and LCC preparations could recover these negative effects by reducing oxidative stress. In zebrafish treated with BPA, carbohydrate-rich LCCs showed stronger antioxidant activity than lignin-rich LCCs, showing their potential as a neuroprotective agents.

Influence of climate change and mechanized harvesting on maize (Zea mays L.) planting and northern limits in northeast China.

BACKGROUND: Northeast China is one of the most important maize producing areas in China. Due to limitations on crop growth resulting from temperature, whether this area can realize mechanical kernel harvesting maize (MKHM) will directly affect the stable development of maize in the region. The effects of climate change on the northern limits of early maturing MKHM were also analyzed in the study. RESULTS: The mean temperature during the maize growth period increased at a rate of 0.22 °C/10a from 1960 to 2018. The average growth periods for early, middle- and late-maturing common harvest maize (CHM) were 123, 135, and 140 days, respectively, and the accumulated temperature above 10 °C (AAT10) was 2400 °C, 2800 °C, and 3100 °C. The early maturing MKHM growth period was about 20 days longer than that of early maturing CHM, and thus the AAT10 of the MKHM was 2700 °C. From 2000-2018, the northern limits for the early maturing CHM maize planting were located from south of Nenjiang and Wudalianchi (47° 98' N-49° 74' N), while the northern limits for the early maturing MKHM maize were located in south Keshan, Nehe, and Hailun (46° 32' N-48° 70' N), which was about 148 km southward compared to the northern limits of the early maturing CHM maize. CONCLUSION: This study not only confirmed the northern limits of early maturing MKHM maize but also indicated that the development of MKHM offsets the influences of climate change on the northern limits of maize planting. This is very important for the sustainable development of maize in the region. © 2020 Society of Chemical Industry.

Facile Construction of a Highly Dispersed Pt Nanocatalyst Anchored on Biomass-Derived N/O-Doped Carbon Nanofibrous Microspheres and Its Catalytic Hydrogenation.

With the depletion of nonrenewable resources and the increasingly serious "white pollution" caused by nondegradable plastics, using renewable biomass resources such as chitin to fabricate materials is a green and sustainable pathway. Herein, for the first time, we used N/O-doped carbon nanofibrous microspheres (CNMs) derived from renewable chitin as carriers to successfully construct a highly dispersed platinum nanocatalyst via a facile way. Various physicochemical characterizations provided reliable evidence for the ultrafine and well-dispersed platinum nanoparticles with an average diameter of 2.3 nm. As the supporting framework, the CNM with interconnected nanofibrous networks and a large surface area facilitated the adhesion and dispersion of Pt particles. Meanwhile, the inherent N/O-containing functional groups and the defects in carbonized chitin could anchor the platinum tightly. The CNM/Pt catalyst was further examined for hydrogenation, and it exhibited promising catalytic activity and stability (∼5 runs, 91%) and a broad applicability. This utilization of biomass resources to build catalyst materials would be important for the green and sustainable chemistry.

Study on Foaming Quality and Impact Property of Foamed Polypropylene Composites.

In the present work, foamed polypropylene (PP) composites were prepared by chemical foaming technology, and the foaming quality and impact property of the foamed PP composites were studied. The results showed that the foaming quality was significantly improved after the introduction of thermoplastic rubber (TPR) and polyolefin elastomer (POE). Meanwhile, it was found that the impact property depended on the intrinsic toughness and contribution of foams (cells) to the PP composites. Furthermore, the data regarding impact property in low temperature showed that when the temperature was between -80 and -20 °C, the impact properties of the foamed PP composites were higher than that of the unfoamed sample, which was due to the impact property being completely contributed by cells under this condition. Meanwhile, when the temperature ranged from -20 to 20 °C, the impact property of the unfoamed sample was higher, which was due to the PP matrix contributing more to the impact property under this temperature. This work significantly improved the foaming quality of foamed PP composites and provided reliable evidence for the improvement of impact property.

[Impacts of high temperature on maize production and adaptation measures in Northeast China].

Heat stress is one of the major agro-meteorological hazards that affect maize production significantly in the farming region of Northeast China (NFR). This study analyzed the temporal and spatial changes of the accumulated temperature above 30 °C (AT) and the accumulated days with the maximum temperature above 30 °C (AD) in different maize growing phases under global warming. It further evaluated the impacts of extreme heat on maize yield in different regions, and put forward some adaptation measures to cope with heat stress for maize production in NFR. The results showed that during 1961 to 2010, the temperature in the maize growing season increased significantly. The maximum temperature in flowering phase was much larger than that in the other growing phases. Temperature increased at rates of 0. 16, 0. 14, 0.06 and 0.23 °C every ten years in the whole maize growing season, vegetative growth phase (from sowing to 11 days before flowering), flowering phase, and late growth phase (from 11 days after flowering to maturity), respectively. The AT in the whole maize growing season increased in NFR during the last 50 years with the highest in the southwest part of NFR, and that in the vegetative growth phase increased faster than in the other two phases. The AD in the whole maize growing season increased during the last 50 years with the highest in the southwest part of NFR, and that in the late growth phase increased faster than in the other two phases. Heat stress negatively affected maize yield during the maize growing season, particularly in the vegetative growth phase. The heat stress in Songliao Plain was much higher in comparison to the other regions. The adaptation measures of maize production to heat stress in NFR included optimizing crop structure, cultivating high temperature resistant maize varieties, improving maize production management and developing the maize production system that could cope with disasters.

Enhancing spoof surface-plasmons with gradient metasurfaces.

The coupling between surface plasmons and free electrons may be used to amplify waves or accelerate particles. Nonetheless, such an interaction is usually weak due to the small interaction length or velocity mismatching. Here a mechanism for enhancing the coupling between plasmonic fields and relativistic electrons is proposed. By using a weakly gradient meta-surface that supports the spoof surface-plasmons (SSP), the phase velocity of SSP mode can be manipulated and quasi-velocity-matching between SSP and electrons may be achieved. The dynamic coupling equations suggest that, due to the strong coupling, the energy can be extracted continuously from the relativistic electrons. The sustained increase of SSP in a narrow frequency band has been demonstrated by the particle-in-cell simulations, where the output power of SSP attains 65 W at 1 THz (with 28 mm interaction length) and the coupling efficiency is enhanced by two orders of magnitude. The results may find potential applications for designing new compact and efficient THz wave sources.

Artificial Kerr-type medium using metamaterials.

We investigated an artificial Kerr-medium realized by actuated THz metamaterials. Instead of directly applying E-field inside the medium, we use micromechanical systems actuated by voltage to tune the phase shift. We established that the combined system can have a relationship between the phase shift and the voltage similar to a Kerr cell. A metamaterial Kerr-cell is designed to modulate the transmission phase difference by 0.99°/V² which is much stronger than natural Kerr crystals. It is attributed to the mechanical tunability of metamaterials with high indices in two orthogonal directions. A Lorentzian model is used in explaining the artificial Kerr cell.

Efficient synthesis of multicyclic spirooxindoles via a cascade Michael/Michael/oxa-Michael reaction of curcumins and isatylidene malononitriles.

A cascade Michael/Michael/oxa-Michael reaction between curcumins and isatylidene malononitriles has been developed. Multicyclic spirooxindoles were prepared in excellent yields and diastereoselectivities. DMAP was found to catalyze this transformation efficiently under mild reaction conditions.