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IntroductionDry matter accumulation (DMA) and dry matter partitioning (DMP) are important physiological processes determining crop yield formation. Deep understanding of the DMA and DMP processes and their responses to drought are limited by difficulty in acquiring total root biomass.MethodsPot experiments with treatments quitting and ceasing ear growth (QC) and controlling soil water (WC) during vegetative (VP) and reproductive (RP) growth stages of maize (Zea mays) were conducted in Jinzhou in 2019 and 2020 to investigate the effects of drought and rewatering on DMW and DMP of different organs.ResultsThe response of DMW of reproductive organ to drought was more sensitive than those of vegetative organs, and was maintained after rehydration. Drought during VP (VPWC) reduced more sharply DMW of stalk than of leaves, and that during RP (RPWC) decreased more substantially leaves DMW. The effect of drought on DMPR was inconsistent with that on DMW for each organ. The DMP patterns of maize in different growth stages have adaptability to some level of water stress, and their responses increased with drought severity. Drought increased significantly DMP rates (DMPRs) of vegetative organs and reduced the ear DMPR and harvest index (HI), attributing to the suppressed photosynthates partitioning into ear and dry matter redistribution (DMRD) of vegetative organs, especially for stalk DMRD decreasing 26%. The persistence of drought impact was related to its occurrence stage and degree as well as the duration during rewatering to maturity. The aftereffect of drought during different growth periods on DMP were various, and that of VPWC enlarged and drastically induced the reduction of HI, also was larger than that of RPWC which demonstrated obvious alleviation in the previous responses of DMP and HI. Root-shoot ratio (RSR) increased under VPWC and RPWC and subsequent rehydration.DiscussionThe DMWs of stalk, roots and leaves were affected by VPWC in order from large to small, and were close to or larger than the controls after rehydration, indicating the compensation effect of rewatering after drought. The DMPRs, RSR AND HI are the important parameters in agricultural production, and are often used as the constants, but in fact they vary with plant growth. In addition, the interannual differences in ear and stalk DMPRs in response to drought were probably caused by the difference in degree and occurrence stage of drought, further reflecting the variation in response of allometry growth among organs to the environment. Besides, the persistence of drought impact was related to the occurrence stage and degree of drought, which is also associated with the duration during rewatering to maturity. Notably, the effect of drought on DMW was inconsistent with that on DMPR for each organ meaning that the two variables should be discussed separately. The QC did not affect total DMW but increased RSR, changed and intensified the effect and aftereffect of RPWC on DMP, respectively, indicating that the DMP pattern and its response to drought occur change under the condition of QC.

To understand the drought response mechanisms of dry matter partitioning of maize, pot experiments under drought conditions were conducted during the vegetative and reproductive growth periods of maize. The aim was to calculate allometric relationships between the dry matter weight of different organs and their responses to drought. Results showed that allometric relationships between the roots, above-ground plant, and total biomass gradually increased with maize growth approaching maturity under a normal water supply. Drought during the vegetative period reinforced allometric relationships during the growth process and after rewatering and increased the size-dependence of the root shoot ratio. However, drought during the reproductive period weakened them. The ear–shoot allometric relationship was more significant during growth than at later growth under normal conditions but strengthened during later growth in those plants suffering droughts during the vegetative and reproductive stages. The ear–shoot allometric relationship and the size-dependence of harvest index at later growth were significantly enhanced by drought during the reproductive period compared to the vegetative period.

Accurate feature identification of drought disaster events is required for proper risk management in agriculture. This study improved the crop water deficit index (CWDI) by including the daily meteorological, crop development stage, soil moisture content, and yield data for 1981–2020 in northeastern China. Two drought characteristic variables (drought duration and intensity) were extracted using the theory of runs to produce the improved crop water deficit index (CWDIwp). Thresholds for the bivariate indicators were also determined for agricultural drought events of varying severity. A joint distribution model for drought variables was constructed based on five types of Archimedean copulas. The joint probability and the joint recurrence period for agricultural drought events were analyzed for drought events with varying intensities in northeast China. The results suggest that the CWDIwp can reliably identify the onset, duration, and intensity of drought events over the study area and can be used to monitor agricultural drought events. The conditional probability of drought intensity (duration) decreased as the drought duration (intensity) threshold increased, whereas the drought recurrence period increased as the threshold for drought duration and intensity rose. In the period (1981–2020), drought intensity in the three Northeastern provinces showed an increasing trend in the order Jilin Province > Liaoning Province > Heilongjiang Province. The spatial distribution of the joint probability and the joint recurrence period was obvious, and the joint probability showed a decreasing distribution trend from west to east. The distribution trend for the joint probability was opposite to that of the joint recurrence period. Furthermore, the areas with high drought probability values corresponded to the areas with low values for the recurrence period, indicating that the drought occurrence probability was higher, and the recurrence period value was lower in the drought-prone areas. The high-risk drought areas (60–87%) were in western Liaoning and western Jilin, with a recurrence period of 1–3 years, whereas the low-risk areas ( moderate drought > severe drought > extreme drought. The order for the recurrence period was light drought < moderate drought < severe drought < extreme drought. The results provide technical support for disaster prevention and mitigation in drought risk management.

Observational data on dry matter accumulation (DMA) and dry matter partitioning (DMP) from the experiment of maize sown on four different dates in a normal year (2012) and three drought years (2014, 2015, 2018) were analyzed to assess the impact of drought and the sowing date on DMA and DMP in different above-ground organs. The phenology of maize was more closely related to the sowing date than to drought. In the normal year, the amount of dry matter in different organs differed slightly among sowing dates, except for those at maturity, and increased linearly after jointing: the dry matter of leaves and stalks increased rapidly before tasselling and the milk stage, respectively, and both increased slowly thereafter, whereas the dry matter of the ears increased linearly. In the drought years, DMA was more sensitive to precipitation relative to the normal year and was affected by the sowing date and drought. Specifically, drought lowered the dry matter of the above-ground organs to varying degrees and accentuated that variation in crops sown on different dates. From the view of DMP, a mild drought lowers the stalk DMP rate but increases the rate in ears. The more severe the drought, the smaller the DMP rate in ears and the stronger the inhibition of the transfer of dry matter from stalk to ears, as well as the more significant difference in the DMP pattern among the sowing dates. High temperatures and drought had a significant synergistic effect on DMAs in all the organs relative to that of drought alone, reversely having an inappreciable impact on the DMP pattern. During the three growth periods, namely jointing to tasselling, tasselling to the milk stage, and the milk stage to maturity, DMA during any two adjacent periods had a clear complementary effect, especially before and after tasselling. Dry matters of the above-ground parts in aggregate, of the stalk and of the ears, at the milk and maturity stages were negatively correlated to the degree of drought, and the maximum correlation was for the ears.

Determining the effects of progressive drought (PD) on dry matter production, partitioning, and grain yield of maize will help in designing a suitable strategy for water management. Though influences of drought on maize growth and development have been investigated extensively, few of them focused on the effects of different duration and occurrence stage of PD on yield formation of maize. Six variations of PD, in the form of withholding irrigation for varying lengths of time from jointing or tasselling, were tested in the field, using a mobile rain shelter, in terms of their effects on aboveground biomass accumulation, partitioning, and grain yield in 2015-2016. The results showed that grain yield was significantly reduced by PD during either vegetative or reproductive stage, and the reduction in grain yield from reproductive PD (41.6-46.6%) was greater than that from vegetative PD (18.6-26.2%). The decrease in grain yield was largely caused by the decrease in kernels per ear (r2 = 0.88, P < 0.001). This research implied that guaranteeing water supply for maize during reproductive stage is crucially important to avoid the reduction in kernels per ear and grain yield.

Northeast China (NEC) is a region sensitive to climate change. However, the adoption of long-season maize cultivars in NEC has caused a substantial yield increase under climate change conditions. It is important to determine whether such cultivar adoptions are effective throughout the whole NEC to sustainably increase grain yield. In this study, phenological observations and meteorological data at six sites from 1981 to 2018 were used to detect thermal time (TT) trends during the maize growing period. TT, as a parameter for measuring changes in maize cultivars, was used in the crop simulation model CERES-Maize to examine the variations in maize yield produced with different cultivar × climate combinations in different decades. In NEC, both TTs from emergence to anthesis and from anthesis to physiological maturity showed significant increasing trends from 1981 to 2018. Simulation results for humid areas revealed that adopting longer-season cultivars during 2000–2018 caused yield increases, ranging from 6.3% to 13.3%, compared with the 1980s. However, for stations in semi-humid areas, maize grain yield showed a decrease or a small increase (from −12.7% to 8.0%) when longer-season cultivars were adopted during 2000–2018. For semi-humid areas, decreasing trends in the ratios of rainfed yield to no water-stress yield (Yrainfed/Yno water-stress) and lower Yrainfed/Yno water-stress values during 2000–2018 indicated a growing sensitivity of maize production to water, which was attributed to changes in TT and precipitation. Our results indicate that, for the semi-humid area, maize yield was limited by water after introducing cultivars with higher TT requirement under climate change conditions. Therefore, securing food supplies will depend on increases in water-use efficiency levels and other adaptive strategies, such as varietal diversification, drought-resistant varieties, conservation tillage and irrigation.

Abstract We are studying the effects of Self-Interacting dark radiation (SIdr) on the evolution of the universe. Our main focus is on the cosmic microwave background (CMB) and how SIdr could potentially help resolve the Hubble tension. We are looking into different scenarios by mixing SIdr with Free-Streaming dark radiation (FSdr) or not to determine whether SIdr can indeed contribute to solving the Hubble tension. We find that SIdr alone can increase the Hubble constant ( $$H_0$$ H 0 ) to $$70.1_{-1.6}^{+1.3}, \text {km/s/Mpc}$$ 70 . 1 - 1.6 + 1.3 , km/s/Mpc with a value of $$N_\textrm{eff}=3.27_{-0.31}^{+0.23}$$ N eff = 3 . 27 - 0.31 + 0.23 . However, including FSdr disfavors the existence of SIdr $${\tilde{N}}_\textrm{si}\approx 0.37$$ N ~ si ≈ 0.37 . Even though the Hubble constant is increased compared to the predicted value, it entails $$N_\textrm{eff}=3.52\pm 0.25$$ N eff = 3.52 ± 0.25 . Finally, we implement the Fisher method for future experiments and a $$7.64\sigma $$ 7.64 σ measurement of $${\tilde{N}}_\textrm{si}$$ N ~ si will be obtained when combing data from Planck, AliCPT, and CMB-S4.

We propose a new probe of primordial non-Gaussianities (NGs) through the observation of gravitational waves (GWs) induced by ultra-light (MPBH

This paper examined impacts of drought on both physiological and dry matter characteristics of spring maize grown in Liaoning, China in 2016. We compared responses of dry matters of various parts, yield components, leaf photosynthesis, and transpiration to four drought levels: RD (no drought treatment), D1 (drought treatment between the 38th and 65th day after sowing), D2 (drought treatment between the 38th and 79th day after sowing), and D3 (drought treatment between the 53rd and 93rd day after sowing). Results indicate that the long-term drought in either jointing period or tasseling period had a severer impact on the dry matters and yield components than the short-term drought in jointing period. Moreover, the dry matters and the corresponding partitioning coefficients of different parts were distinct. The yield reduction was caused by the decreases of ear length and bald tip ratio during the short-term drought at jointing period, while it was caused by the reductions of ear length, ear diameter, and grain number per spike during the long-term drought in jointing and tasseling periods. Responses of leaf photosynthesis and transpiration to drought were lagging, but reactions of tasseling drought were faster. Leaf photosynthesis and transpiration after a short-term drought in jointing period could recover to an average level but that after the long-term drought in either jointing or tasseling period could not, after irrigation.

Roots are an important water transport pathway between soil and plant. Root water uptake (RWU) plays a key role in water and heat exchange between plants and the atmosphere. Inaccurate RWU schemes in land surface models are one crucial reason for decreased model performance. Despite some types of RWU functions being adopted in land surface models, none have been certified as suitable for maize farmland ecosystems. Based on 2007–2009 data observed at the maize agroecosystem field station in Jinzhou, China, the RWU function and root distribution (RD) in the Common Land Model (CoLM) were optimized and the effects of the optimizations on model performance were compared. Results showed that RD parameters calculated with root length density were more practical relative to root biomass in reflecting soil water availability, and they improved the simulation accuracy for water and heat fluxes. The modified RWU function also played a significant role in optimizing the simulation of water and heat fluxes. Similarly, the respective and integrated roles of two optimization schemes in improving CoLM performance were significant during continuous non-precipitation days, especially during the key water requirement period of maize. Notably, the improvements were restrained within a threshold of soil water content, and the optimizations were inoperative outside this threshold. Thus, the optimized RWU function and the revised RD introduced into the CoLM model are applicable for simulation of water and heat fluxes for maize farmland ecosystems in arid areas.

This paper presents various experimental verifications for the theoretical analysis results of vibration suppression to a smart flexible beam bonded with a piezoelectric actuator by a velocity feedback controller and an extended state observer (ESO). During the state feedback control (SFC) design process for the smart flexible beam with the pole placement theory, in the state feedback gain matrix, the velocity feedback gain is much more than the displacement feedback gain. For the difference between the velocity feedback gain and the displacement feedback gain, a modified velocity feedback controller is applied based on a dynamical model with the Hamilton principle to the smart beam. In addition, the feedback velocity is attained with the extended state observer and the displacement is acquired by the foil gauge on the root of the smart flexible beam. The control voltage is calculated by the designed velocity feedback gain multiplied by the feedback velocity. Through some experiment verifications for simulation results, it is indicated that the suppressed amplitude of free vibration is up to 62.13% while the attenuated magnitude of its velocity is up to 61.31%. Therefore, it is demonstrated that the modified velocity feedback control with the extended state observer is feasible to reduce free vibration.

Current researches on temporal networks mainly tend to detect community structure. A number of community detection algorithms can obtain community structure on each time slice or each period of time but rarely present the evolution of community structure. Some papers discussed the process of community structure evolution but lacked quantifying the evolution. In this paper, we put forward the concept of Community Vitality (CV), which shows a community's life intensity on a time slice. In the process of computing CV, the “dead communities” can also be distinguished. Moreover, CV cannot only be used to quantify the life intensity of a community but also be used to describe the process of community evolution over time. More specifically, the change of community's structure will be found if CVs for different time slices of a community were compared, while the community with big value of CV can be selected if CVs for different communities were compared. Furthermore, community vitality change rate (CVCR) is proposed for revealing communities' structure change. The results of our experiments show that community vitality is a novel and effective way to understand or model the community evolution.

Establishing high performance cooperation and estimating nodes’ risk level in mobile ad hoc networks (MANETs) are currently fundamental and challenging due to the inherent characteristics of MANETs, such as the highly dynamic topology and the absence of an effective security mechanism. Trust based assessment methods were recently put forward but presumed restrictions to the data samples or presumed weights for node’s attributes are required. In this paper, Projection Pursuit based Risk Assessment (PPRA), is proposed to analyze node’s creditability. As projection pursuit turns high-dimensional node properties to low-dimension space, all nodes’ risk levels could be clustered effectively and accurately. Projection index, the same as judgment index of clustering consequence, is utilized to reveal the behavior of different nodes. By maximizing projection index through Genetic Algorithm (GA), optimal projection direction is obtained, and then the projection values of each node could be calculated. Finally, the results in one-dimension or two-dimension projection space show that our method is more efficient and practical than traditional methods.

Hypericum beanii N. Robson, a perennial upright herb, predominantly inhabits temperate regions. This species has been utilized for the treatment of various inflammation-related diseases. One new xanthone 3,7-dihydroxy-1,6-dimethoxyxanthone (1) and twenty-three known xanthones (2–24) were isolated from the aerial parts of H. beanii. The structure of the new compound was determined based on high-resolution electrospray ionization mass spectroscopy (HR-ESIMS), nuclear magnetic resonance (NMR), Infrared Spectroscopy (IR), ultraviolet spectrophotometry (UV) spectroscopic data. The anti-inflammatory effects of all the isolates were assessed by measuring the inhibitory effect on nitric oxide (NO) production in LPS-stimulated RAW 264.7 macrophages. Compounds 3,4-dihydroxy-2-methoxyxanthone (15), 1,3,5,6-tetrahydroxyxanthone (19), and 1,3,6,7-tetrahydroxyxanthone (22) exhibited significant anti-inflammatory effects at a concentration of 10 μM with higher potency compared to the positive control quercetin. Furthermore, compounds 15, 19, and 22 reduced inducible NO synthase (iNOS), tumor necrosis factor alpha (TNF-α), interleukin-1β (IL-1β), IL-6, and cyclooxygenase 2 (COX-2) mRNA expression in the LPS-stimulated RAW 264.7 macrophages, suggesting that these compounds may mitigate the synthesis of the aforementioned molecules at the transcriptional level, provisionally confirming their anti-inflammatory efficacy.

Given a target binary function, the binary code search retrieves top-K similar functions in the repository, and similar functions represent that they are compiled from the same source codes. Searching binary code is particularly challenging due to large variations of compiler tool-chains and options and CPU architectures, as well as thousands of binary codes. Furthermore, there are some pivotal issues in current binary code search schemes, including inaccurate text-based or token-based analysis, slow graph matching, or complex deep learning processes. In this paper, we present an unsupervised tensor embedding scheme, Codee, to carry out code search efficiently and accurately at the binary function level. First, we use an NLP-based neural network to generate the semantic-aware token embedding. Second, we propose an efficient basic block embedding generation algorithm based on the network representation learning model. We learn both the semantic information of instructions and the control flow structural information to generate the basic block embedding. Then we use all basic block embeddings in a function to obtain a variable-length function feature vector. Third, we build a tensor to generate function embeddings based on the tensor singular value decomposition, which compresses the variable-length vectors into short fixed-length vectors to facilitate efficient search afterward. We further propose a dynamic tensor compression algorithm to incrementally update the function embedding database. Finally, we use the local sensitive hash method to find the top-KK similar matching functions in the repository. Compared with state-of-the-art cross-optimization-level code search schemes, such as Asm2Vec and DeepBinDiff, our scheme achieves higher average search accuracy, shorter feature vectors, and faster feature generation performance using four datasets, OpenSSL, Coreutils, libgmp and libcurl. Compared with other cross-platform and cross-optimization-level code search schemes, such as Gemini, Safe, the average recall of our method also outperforms others.

In our research on naturally occurring sesquiterpenes, eight shizukaol-type dimers, one chlorahololide-type dimer, and one sarcanolide-type dimer were isolated from the roots of Chloranthus fortunei. As the project was implemented, we accidentally discovered that shizukaol-type dimers can be converted into peroxidized chlorahololide-type dimers. This potential change was discovered after simulations of the changes in corresponding shizukaols showed that three peroxide products were generated (1–3), indicating that peroxidation reactions occurred. HPLC-HR-MS analysis results obtained for the shizukaol derivatives further demonstrate that the reaction occurred, and the type of substituent of small organic ester moieties at positions C-15’ and C-13’ of unit B were not decisively related to the reaction. Quantum chemical calculations of the mode dimer further demonstrated this phenomenon. The highest occupied molecular orbital (HOMO)–lowest unoccupied molecular orbital (LUMO) energy of the precursor and production revealed the advantageous yield of 4β-hydroperoxyl production. Additionally, the potential reaction mechanism was speculated and validated using the free energy in the reaction which successfully explained the feasibility of the reaction. Finally, the anti-inflammatory activity of the precursors and products was evaluated, and the products of peroxidation showed better anti-inflammatory activity.

In this article we confront a class of f ( Q ) gravity models with observational data of galaxy–galaxy lensing. Specifically, we consider f ( Q ) gravity models containing a small quadratic correction when compared with general relativity (GR), and quantify this correction by a model parameter, α . To derive the observational constraints, we start by extracting spherically symmetric solutions, which correspond to deviations from the Schwarzschild solution that depends on the model parameters in a twofold way, i.e., a renormalized mass and a new term proportional to r ^−2 . Then, we calculate the effective lensing potential, the deflection angle, the shear component, and the effective excess surface density profile. After that, we employ a group catalog and a shape catalog from the Sloan Digital Sky Survey Data Release 7 for the lens and source samples, respectively. Moreover, we handle the off-center radius as a free parameter and constrain it using a Markov Chain Monte Carlo method. Concerning the deviation parameter from GR we derive $\alpha ={1.202}_{-0.179}^{+0.277}\times {10}^{-6}\ {\mathrm{Mpc}}^{-2}$ at the 1 σ confidence level, and then compare the fitting efficiency with the standard Λ cold dark matter paradigm by applying the Akaike information criterion and Bayesian information criterion. Our results indicate that the f ( Q ) corrections alongside the off-center effect yield a scenario that is slightly favored.

We study the impact of warm dark matter (WDM) mass on the internal properties of individual galaxies using a large suite of 1024 state-of-the-art cosmological hydrodynamic simulations from the DREAMS project. We take individual galaxies’ properties from the simulations, which have different cosmologies, astrophysics, and WDM masses, and train normalizing flows to learn the posterior of the parameters. We find that our models cannot infer the value of the WDM mass, even when the values of the cosmological and astrophysical parameters are given explicitly. This result holds for galaxies with stellar mass larger than 2 × 10 ^8 M _⊙ h ^−1 at both low and high redshifts. We calculate the mutual information and find no significant dependence between the WDM mass and galaxy properties. On the other hand, our models can infer the value of Ω _m with a ∼10% accuracy from the properties of individual galaxies while marginalizing astrophysics and WDM masses.

We use galaxy–galaxy lensing data to test general relativity and f ( T ) gravity at galaxy scales. We consider an exact spherically symmetric solution of f ( T ) theory, which is obtained from an approximate quadratic correction, and thus it is expected to hold for every realistic deviation from general relativity. Quantifying the deviation by a single parameter Q , and following the post-Newtonian approximation, we obtain the corresponding deviation in the gravitational potential, shear component, and effective excess surface density profile. We used five stellar mass samples and divided them into blue and red galaxies to test the model dependence on galaxy color, and we modeled the excess surface density profiles using the Navarro–Frenk–White profiles. Based on the group catalog from the Sloan Digital Sky Survey Data Release 7 (SDSS DR7) we finally extract $Q=-{2.138}_{-0.516}^{+0.952}\times {10}^{-5}\,$ Mpc ^−2 at 1 σ confidence. This result indicates that f ( T ) corrections on top of general relativity are favored. Finally, we apply information criteria, such as the Akaike and Bayesian ones, and although the dependence of f ( T ) gravity on the off-center effect implies that its optimality needs to be carefully studied, our analysis shows that f ( T ) gravity is more efficient in fitting the data compared to general relativity and the ΛCDM paradigm, and thus it offers a challenge to the latter.

One hitherto unknown protoilludane-type sesquiterpene, 8 β -hydroxyepicoterpene D (1), along with two novel prenylated aromatic compounds, namely coriolopsisins A and B (2 – 3), were isolated from the ethanol extract of Coriolopsis trogii fruit body. Their structures were determined through extensive spectroscopic data analysis and comparison of experimental and calculated electronic circular dichroism data. Compounds 2 and 3 are rare examples in which the isopentenyl group is attached to the side chain of the aromatic ring rather than directly to the aromatic ring, containing succinimide and alkynyl segments, respectively. Plausible biosynthetic pathways of compounds 2 and 3 are proposed and unique aromatic prenyltransferases may exist. [Display omitted] • One protoilludane-type sesquiterpene and two prenylated aromatic compounds were isolated from Coriolopsis trogii. • 8 β -Hydroxyepicoterpene D (1) was a novel a split-ring protoilludane-type sesquiterpenoid. • Coriolopsisins A and B (2 and 3) were rare examples containing succinimide and alkynyl segments, respectively. • The structures were established via extensive analyses of the spectroscopic data and ECD data. • Plausible biosynthetic pathways of coriolopsisins A and B (2 and 3) are proposed. [ABSTRACT FROM AUTHOR]