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Background Pulmonary hypertension is a rare, progressive disorder that can lead to right ventricular hypertrophy, right heart failure, and even sudden death. N6‐methyladenosine modification and the main methyltransferase that mediates it, methyltransferase‐like (METTL) 3, exert important effects on many biological and pathophysiological processes. However, the role of METTL3 in pyroptosis remains unclear. Methods and Results Here, we characterized the role of METTL3 and the underlying cellular and molecular mechanisms of pyroptosis, which is involved in pulmonary hypertension. METTL3 was downregulated in a pulmonary hypertension mouse model and in hypoxia‐exposed pulmonary artery smooth muscle cell. The small interfering RNA–induced silencing of METTL3 decreased the m6A methylation levels and promoted pulmonary artery smooth muscle cell pyroptosis, mimicking the effects of hypoxia. In contrast, overexpression of METTL3 suppressed hypoxia‐induced pulmonary artery smooth muscle cell pyroptosis. Mechanistically, we identified the phosphate and tension homology deleted on chromosome 10 (PTEN) gene as a target of METTL3‐mediated m6A modification, and methylated phosphate and tension homology deleted on chromosome 10 mRNA was subsequently recognized by the m6A “reader” protein insulin‐like growth factor 2 mRNA‐binding protein 2, which directly bound to the m6A site on phosphate and tension homology deleted on chromosome 10 mRNA and enhanced its stability. Conclusions These results identify a new signaling pathway, the METTL3/phosphate and tension homology deleted on chromosome 10/insulin‐like growth factor 2 mRNA‐binding protein 2 axis, that participates in the regulation of hypoxia‐induced pyroptosis.

The stimulator of interferon genes (STING), an integral adaptor protein in the DNA-sensing pathway, plays a pivotal role in the innate immune response against infections. Additionally, it presents a valuable therapeutic target for infectious diseases and cancer. We observed that fangchinoline (Fan), a bis-benzylisoquinoline alkaloid (BBA), effectively impedes the replication of vesicular stomatitis virus (VSV), encephalomyocarditis virus (EMCV), influenza A virus (H1N1), and herpes simplex virus-1 (HSV-1) in vitro. Fan treatment significantly reduced the viral load, attenuated tissue inflammation, and improved survival in a viral sepsis mouse model. Mechanistically, Fan activates the antiviral response in a STING-dependent manner, leading to increased expression of interferon (IFN) and interferon-stimulated genes (ISGs) for potent antiviral effects in vivo and in vitro. Notably, Fan interacts with STING, preventing its degradation and thereby extending the activation of IFN-based antiviral responses. Collectively, our findings highlight the potential of Fan, which elicits antiviral immunity by suppressing STING degradation, as a promising candidate for antiviral therapy.

Pulmonary hypertension (PH) is an extremely malignant pulmonary vascular disease of unknown etiology. ADAR1 is an RNA editing enzyme that converts adenosine in RNA to inosine, thereby affecting RNA expression. However, the role of ADAR1 in PH development remains unclear. In the present study, we investigated the biological role and molecular mechanism of ADAR1 in PH pulmonary vascular remodeling. Overexpression of ADAR1 aggravated PH progression and promoted the proliferation of pulmonary artery smooth muscle cells (PASMCs). Conversely, inhibition of ADAR1 produced opposite effects. High-throughput whole transcriptome sequencing showed that ADAR1 was an important regulator of circRNAs in PH. CircCDK17 level was significantly lowered in the serum of PH patients. The effects of ADAR1 on cell cycle progression and proliferation were mediated by circCDK17. ADAR1 affects the stability of circCDK17 by mediating A-to-I modification at the A5 and A293 sites of circCDK17 to prevent it from m1A modification. We demonstrate for the first time that ADAR1 contributes to the PH development, at least partially, through m1A modification of circCDK17 and the subsequent PASMCs proliferation. Our study provides a novel therapeutic strategy for treatment of PH and the evidence for circCDK17 as a potential novel marker for the diagnosis of this disease.

Partial discharge (PD) is a crucial and intricate electrical occurrence observed in various types of electrical equipment. Identifying and characterizing PDs is essential for upholding the integrity and reliability of electrical assets. This paper proposes an ensemble methodology aiming to strike a balance between the model complexity and the predictive performance in PD pattern recognition. A simple convolutional neural network (SCNN) was constructed to efficiently decrease the model parameters (quantities). A quadratic support vector machine (QSVM) was established and ensembled with the SCNN model to effectively improve the PD recognition accuracy. The input for QSVM consisted of the circular local binary pattern (CLBP) extracted from the enhanced image. A testing prototype with three types of PD was constructed and 3D phase-resolved pulse sequence (PRPS) spectrograms were measured and recorded by ultra-high frequency (UHF) sensors. The proposed methodology was compared with three existing lightweight CNNs. The experiment results from the collected dataset emphasize the benefits of the proposed method, showcasing its advantages in high recognition accuracy and relatively few mode parameters, thereby rendering it more suitable for PD pattern recognition on resource-constrained devices.

The dependable functioning of switchgear is essential to maintain the stability of power supply systems. Partial discharge (PD) is a critical phenomenon affecting the insulation of switchgear, potentially leading to equipment failure and accidents. PDs are generally grouped into metal particle discharge, suspended discharge, and creeping discharge. Different types of PDs are closely related to the severity of a PD. Partial discharge pattern recognition (PDPR) plays a vital role in the early detection of insulation defects. In this regard, a Back Propagation Neural Network (BPNN) for PDPR in switchgear is proposed in this paper. To eliminate the sensitivity to initial values of BPNN parameters and to enhance the generalized ability of the proposed BPRN, an improved Mantis Search Algorithm (MSA) is proposed to optimize the BPNN. The improved MSA employs some boundary handling strategies and adaptive parameters to enhance the algorithm’s efficiency in optimizing the network parameters of BPNN. Principal Component Analysis (PCA) is introduced to reduce the dimensionality of the feature space to achieve significant time saving in comparable recognition accuracy. The initially extracted 14 feature values are reduced to 7, reducing the BPNN parameter count from 183 with 14 features to 113 with 7 features. Finally, numerical results are presented and compared with Decision Tree (DT), k-Nearest Neighbor classifiers (KNN), and Support Vector Machine (SVM). The proposed method in this paper exhibits the highest recognition accuracy in metal particle discharge and suspended discharge.

Abstract Background Pyroptosis is a form of programmed cell death involved in the pathophysiological progression of hypoxic pulmonary hypertension (HPH). Emerging evidence suggests that N6-methyladenosine (m6A)-modified transcripts of long noncoding RNAs (lncRNAs) are important regulators that participate in many diseases. However, whether m6A modified transcripts of lncRNAs can regulate pyroptosis in HPH progression remains unexplored. Methods The expression levels of FENDRR in hypoxic pulmonary artery endothelial cells (HPAECs) were detected by using quantitative real-time polymerase chain reaction (qRT-PCR) and fluorescence in situ hybridization (FISH). Western blot, Lactate dehydrogenase (LDH) release assay, Annexin V-FITC/PI double staining, Hoechst 33342/PI fluorescence staining and Caspase-1 activity assay were used to detect the role of FENDRR in HPAEC pyroptosis. The relationship between FENDRR and dynamin-related protein 1 (DRP1) was explored using bioinformatics analysis, Chromatin Isolation by RNA Purification (CHIRP), Electrophoretic mobility shift assay (EMSA) and Methylation-Specific PCR (MSP) assays. RNA immunoprecipitation (RIP) and m6A dot blot were used to detect the m6A modification levels of FENDRR. A hypoxia-induced mouse model of pulmonary hypertension (PH) was used to test preventive effect of conserved fragment TFO2 of FENDRR. Results We found that FENDRR was significantly downregulated in the nucleus of hypoxic HPAECs. FENDRR overexpression inhibited hypoxia-induced HPAEC pyroptosis. Additionally, DRP1 is a downstream target gene of FENDRR, and FENDRR formed an RNA–DNA triplex with the promoter of DRP1, which led to an increase in DRP1 promoter methylation that decreased the transcriptional level of DRP1. Notably, we illustrated that the m6A reader YTHDC1 plays an important role in m6A-modified FENDRR degradation. Additionally, conserved fragment TFO2 of FENDEE overexpression prevented HPH in vivo. Conclusion In summary, our results demonstrated that m6A-induced decay of FENDRR promotes HPAEC pyroptosis by regulating DRP1 promoter methylation and thereby provides a novel potential target for HPH therapy.

Eusocial insects have evolved specific defensive strategies to protect their colonies. In termite colonies, soldiers perform a colony-level defense by displaying mechanical biting, head-banging and mandible opening–closing behaviors. However, few studies have been reported on the factors modulating defensive behaviors in termites. Owing to JH (juvenile hormone) being involved in soldier differentiation, JH was speculated to affect defensive behaviors in termite soldiers. To determine the effect of JH on the defensive behaviors of termite soldiers, we performed a JHA-feeding and RaSsp1-silencing experiment and then tested the changes in defense-related behaviors, alarm pheromones and key JH signaling genes. The observed result was that after feeding workers with JHA, soldiers displayed the following: (1) decreased biting events and increased head-banging events; (2) a reduced expression of RaSsp1 and increased expression of Met (methoprene-tolerant, the nuclear receptor of JH) and Kr-h1 (the JH-inducible transcription factor Krüppel homolog 1); and (3) a decreased concentration of alarm pheromones, including α-pinene, β-pinene and limonene (+, −). Further study showed that soldiers silenced for RaSsp1 also exhibited (1) decreased biting events and increased head-banging events and (2) increased expression of Met and Kr-h1. In addition, soldiers stimulated by the alarm pheromone limonene displayed an increase in the frequency of mandible opening–closing and biting behavior. All of these results show that JHA influenced the defensive behaviors of termite soldiers, possibly via downregulating RaSsp1 expression, up-regulating Met and Kr-h1 and stimulating the secretion of alarm pheromones, suggesting that the JH pathway plays important roles in modulating social behaviors in termite colonies.

Pyroptosis is involved in pulmonary hypertension (PH); however, whether this process is regulated by long non-coding RNAs (lncRNAs) is unclear. Some lncRNAs encode peptides; therefore, whether the regulation of pyroptosis in PH depends on lncRNAs themselves or their encoded peptides needs to be explored. We aimed to characterize the role of the peptide RPS4XL encoded by lnc-Rps4l and its regulatory mechanisms during pyroptosis in PH. Transgenic mice overexpression of lnc-Rps4l was established to rescue the inhibition of hypoxia-induced pyroptosis in pulmonary artery smooth muscle cells (PASMCs). An adeno-associated virus 9 construct with a mutation in the open reading frame of lnc-Rps4l was used to verify that it could inhibit hypoxia-induced PASMCs pyroptosis through its encoded peptide RPS4XL. Glutathione S-transferase (GST) pull-down assays revealed that RPS4XL bound to HSC70, and microscale thermophoresis (MST) was performed to determine the HSC70 domain that interacted with RPS4XL. Through glycosylation site mutation, we confirmed that RPS4XL inhibited hypoxia-induced PASMCs pyroptosis by regulating HSC70 glycosylation. Our results showed that RPS4XL inhibits pyroptosis in a PH mouse model and hypoxic PASMCs by regulating HSC70 glycosylation. These results further clarify the important mechanism of vascular remodeling in PH pathology.

Developing a new and efficient catalytic route for the production of alkanes by upgrading the aqueous phenolic biofuels still remains a challenge. Here, we designed and synthesized a bifunctional catalyst that uses natural montmorillonite (MMT) as support and combines metal active sites and Brӧnsted acid sites in the MMT via ion exchange and reduction roasting process. The catalytic activity of the as-synthesized Pd-MMT (H+) was evaluated by the hydrodeoxygenation (HDO) of a series of lignin-derived phenolic compounds in water. Our model reaction study reveals that the HDO of phenol undergoes an initial hydrogenation of aromatic rings to produce cyclohexanol and cyclohexanone, followed by the dehydration of cyclohexanol to provide intermediate cyclohexene and a final hydrogenation of cyclohexene to create a cyclohexane product. The combination of high metal catalytic activity and Brӧnsted acidity in Pd-MMT (H+) synergistically accelerated the HDO of phenol. Furthermore, good catalytic activity and recycling ability were also observed for other lignin-derived phenolic compounds.

Reduced-dimensional halide perovskites are promising for light-emitting diodes but suffer from photo-degradation. Here Quan et al. identify the edge of the perovskite nanoplatelets as the degradation channels and use phosphine oxides to passivate the edges and boost device performance and lifetime.

Based on the job demands-resources model, this study explored the relationships of work engagement, job performance and psychological capital in industry employees. A total of 399 IT programmers were recruited and completed the work engagement scale, knowledge employee job performance scale and psychological capital questionnaire. The results showed that: (1) There is a relationship between work engagement and job performance, which may not be linear but inverted U-shaped, and (2) psychological capital plays a moderating role in the inverted U-shaped relationship between work engagement and job performance.

The biogeographic characteristics of soil microbial biomass stoichiometry homeostasis and also its mechanisms are commonly thought to be key factors for the survival strategies and resource utilization of soil microbes under extreme habitat. In this work, we conducted a 5,000-km transect filed survey in alpine grassland across Qinghai–Tibet Plateau in 2015 to measure soil microbial biomass carbon (MBC) and nitrogen (MBN) across alpine steppe and meadow. Based on the differences of climate and soil conditions between alpine steppe and meadow, the variation coefficient was calculated to investigate the homeostatic degree of MBC to MBN. Furthermore, the “trade-off” model was utilized to deeply distinguish the homeostasis degree of MBC/MBN between alpine steppe and meadow, and the regression analysis was used to explore the variability of trade-off in response to environmental factors in the alpine grassland. The results showed that the coefficient of variation (CV) of MBC/MBN in alpine meadow (CV = 0.4) was lower than alpine steppe (CV = 0.7). According to the trade-off model, microbial turnover activity of soil N relative to soil C increased rapidly and then decreased slightly with soil organic carbon (SOC), soil total nitrogen (STN), and soil water content across alpine meadow. Nevertheless, in alpine steppe, SOC/STN had a positive effect on microbial turnover of soil N. These results suggested that water, heat, and soil nutrients availability were the key factors affecting the C:N stoichiometry homeostasis of soil microbial biomass in Qinghai–Tibet Plateau (QTP)’s alpine grassland. Since the difference of survival strategy of the trade-off demands between soil C and N resulting in different patterns and mechanism, the stoichiometry homeostasis of soil microbial biomass was more stable in alpine meadow than in alpine steppe.

Freezing and thawing indices (FI and TI) are commonly used as indicators for climate change assessment and permafrost extent estimation in cold regions. In this study, based on the meteorological daily data (1978–2017) among 34 meteorological stations in Tibet, the temperature in space has been interpolated and FI and TI have been calculated. Finally, spatiotemporal variations have been analyzed and the permafrost area has been estimated. The results showed the mean annual of FI and TI in Tibet are 1241.36 and 1290.22°C⋅day, respectively. A significant downward trend in freezing index (FI) and an upward trend in thawing index (TI) have been reported in the time series, in against, analyzing the spatial distribution showed there is an increasing trend from southeast to northwest for FI while TI was decreased gradually in the same region in Tibet. This research indicates that altitude has a significant influence on the change of FI and TI. With the increase of altitude, FI decreased and TI increased more significantly. The permafrost area was estimated at about 0.59 × 106 km2 in Tibet.

Abstract Background The diamondback moth (DBM), Plutella xylostella (L.), is a major pest of cruciferous crops worldwide. While the species has become a model for genomics, post-transcriptional mechanisms associated with development and sex determination have not been comprehensively studied and the lack of complete structure of mRNA transcripts limits further research. Results Here, we combined the methods of single-molecule long-read sequencing technology (IsoSeq) and RNA-seq to re-annotate the published DBM genome and present the genome-wide identification of alternative splicing (AS) associated with development and sex determination of DBM. In total, we identified ~ 13,900 genes (~ 77%) annotated in the DBM genome (version-2), resulting in the correction of 1586 wrongly annotated genes and identification of 78,000 previously unannotated transcripts. We also identified 1804 genes showing alternative splicing (AS) in each of the developmental stages and sexes, suggesting that AS events are ubiquitous in DBM. Comparative analyses showed that these AS events were rarely shared among developmental stages, indicating that they may play key specific roles in regulation of insect development. Further, we found 156 genes showing different AS events and expression patterns between males and females, linking them to potential functions in sex determination. Conclusion Overall, the P. xylostella transcriptome provides the significant information about regulatory alternative splicing events, which are shown to be involved in development and sex determination. Our work presents a solid foundation to better understand the mechanism of post-transcriptional regulation, and offers wider insights into insect development and sex determination.

Biological invasion pose a severe threat to global biodiversity, and studies of bioinvasion patterns and the underlying mechanisms provide critical tests to ecological theories. China is a global hotspot of biodiversity and also biological invasions. The understanding of mechanisms for bioinvasion patterns has been limited by inadequacy of data spatial resolution, and lack of a historical perspective. This study compiled the first nation-scale distribution data with a sub-provincial spatial unit (prefecture) for 463 invasive alien plants species (IAPS) recorded in China, as well as their introduction times. The spatiotemporal patterns of species richness of invasive alien plants, including three life forms (annual-biennial, perennial, and woody) were explored, then related the species richness patterns with environmental, social-economic and historical factors. Statistical analyses included quantile regression, generalized linear model (GLM), and hierarchical variation partitioning. The results indicated that: (1) herbaceous species comprised 84% of the 463 IAPS in China; (2) plant introductions into China accelerated since 1800, reaching the maximum rate during 1900–1940. IAPS richness had a closer correlation with the time of newest introduction (R2 = 0.155) than with that of the oldest introduction (R2 = 0.472); (3) IAPS richness decreases with increasing latitude (r = −0.32, P < 0.001) and decreases from the coastal and southern terrestrial borders to inland regions, but doesn’t increase with prefecture size. The three life forms of IAPS showed similar latitudinal patterns of species richness and divergent latitudinal patterns of species percentage. (4) IAPS richness showed significantly positive correlations with thermal climate and a negative relationship with climate seasonality. GLM explained up to 65% of the variation in spatial patterns of IAPS and three life forms; with much less variation explained in the species percentage patterns. The year of the most recent IAPS introduction and the low temperature limit jointly dominated spatial patterns of IAPS richness in China, whereas road density showed little effect. Therefore, global warming and economic globalization play a prominent role in promoting biological invasion in the last few decades, and will continue to drive the trend of plant invasion in China and probably elsewhere.

Termite soldiers are a unique caste among social insects, and their differentiation can be induced by Juvenile hormone (JH) from workers through two molts (worker–presoldier–soldier). However, the molecular mechanism underlying the worker-to-soldier transformation in termites is poorly understood. To explore the mechanism of soldier differentiation induced by JH, the gene soldier caste-specific protein 1 (RaSsp1, NCBI accession no: MT861054.1) in R. aculabialis was cloned, and its function was studied. This gene was highly expressed in the soldier caste, and the protein RsSsp1 was similar to the JHBP (JH-binding protein) domain-containing protein by Predict Protein online. In addition, JHIII could be anchored in the hydrophobic cage of RaSsp1 as the epoxide of the JHBP-bound JH according to the protein ligand molecular docking online tool AutoDock. The functional studies indicated that knocking down of the RaSsp1 shorted the presoldier’s head capsule, reduced mandible size, delayed molting time and decreased molting rate (from worker to presoldier) at the beginning of worker gut-purging. Furthermore, knocking down of the RaSsp1 had a more pronounced effect on soldier differentiation (from presoldier to soldier), and manifested in significantly shorter mandibles, rounder head capsules, and lower molting rate (from worker to presoldier) at the beginning of presoldier gut-purging. Correspondingly, the expressions of JH receptor Methoprene-tolerant (Met), the JH-inducible transcription factor Krüppel homolog1 (Kr-h1) and ecdysone signal genes Broad-complex (Br-C) were downregulated when knocking down the RaSsp1 at the above two stages. All these results that RaSsp1 may be involved in soldier differentiation from workers by binding and transporting JH.

In China, aging is becoming an increasingly serious issue, and the Chinese government are paying more attention to the life satisfaction of the elderly. Nevertheless, in their daily lives, the elderly are often discriminated against, which may have a negative impact on their life satisfaction. To enable a better understanding of these relationships, we discuss the factors affecting the macro-system (national identity) and micro-system (sense of community) of the elderly. Three hundred and ninety-one elderly people (60–101 years old; 121 males, 270 females) from three communities in the Anhui and Shandong provinces of China participated in our study. Each participant completed the appropriate questionnaires, including: perceived discrimination measure, national identity questionnaire, sense of community questionnaire, and life satisfaction questionnaire. The results of structural equation modeling revealed that perceived discrimination negatively influenced life satisfaction through national identity and community. Perceived discrimination was found to negatively predict national identity, suggesting that perceived discrimination brings a negative influence to national identity within Chinese culture. The relationship between perceived discrimination and life satisfaction was partially mediated by the chain of national identity and sense of community. The size of the total mediation effect was 32.17%. The relationship between perceived discrimination and life satisfaction, when mediated by national identity or sense of community, was not significant. This suggests that the application of the rejection-identification model to the elderly in China may produce different results. The limitations and the implications of our study were considered in discussion.

Post-fire succession is an ideal case for studying effects of disturbance on community assembly, and the key is to disentangle the contributions of assembly processes to the variation of community composition, namely beta diversity, and the contingent scales. The central Yunnan Plateau of Southwest China is characterized by monsoon related seasonal drought, and frequent forest fires. We sampled five fire sites burned in different years and a middle aged forest, measured species composition dissimilarity and its species turnover and nestedness components, within each fire site and across all sites. Results indicated species turnover as the primary component of beta diversity within all communities. There was no trend of change with year-since-fire (YSF) in beta diversity among early post-fire communities, but beta diversity in the middle aged community was significantly higher. Species turnover patterns across fire sites revealed a weak dispersal limit effect, which was stronger at lower than upper slope position for woody plants, and reverse for herbs. At the site scale, the species dissimilarity and turnover both enlarged with increasing slope position difference, especially in the middle-aged community, but the species nestedness had no consistent trend among sites, except a decreasing trend in the middle-aged forest. (Partial) Mantel tests indicated habitat filtering [primarily indicating total nitrogen (TN) and slope position] played a much stronger role than dispersal limit and YSF (indicating competition intensity) for the post-fire forest assembly at the landscape scale, for both woody and herbaceous layers. However, at the site scale, Mantel tests indicated a diminishing effect of soil nutrient filtering with increasing YSF, while effects of topography and spatial distance in the middle aged community was stronger. This divergence suggests the primary assembly mechanism gradually shift away from the soil constraint. While the seasonal drought and the mountain topography dominate the environmental legacy, our results imply that fires may reinforce a priority effect in the forests assembly in this region, by creating a habitat filtering (e.g., moisture and nitrogen limitation) effect on species composition in post-fire communities.

Xyloketals, a new type of antioxidants from a marine mangrove fungus, have potential pharmacological properties. In this paper, the radical-scavenging activities of a series of synthetic xyloketals and related chromanes toward 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) were evaluated by absorption spectrometry. One of the compounds (compound 10) displayed significant antioxidative action against DPPH and ABTS. A structure-activity analysis showed that the reactive sites on these compounds correlated with a hydroxy-group and also with ketal or aromatic H substituents. Based in part on a density functional theory (DFT) calculation of compound 10, the antioxidant mechanism of this chromane was deduced as a possible radical-scavenging mechanism by a sequential proton loss electron-transfer (SPLET) process.

Energy and agricultural commodities and markets have been examined extensively, albeit separately, for a number of years. In the energy literature, the returns, volatility and volatility spillovers (namely, the delayed effect of a returns shock in one asset on the subsequent volatility or covolatility in another asset), among alternative energy commodities, such as oil, gasoline and ethanol across different markets, have been analysed using a variety of univariate and multivariate models, estimation techniques, data sets, and time frequencies. A similar comment applies to the separate theoretical and empirical analysis of a wide range of agricultural commodities and markets. Given the recent interest and emphasis in bio-fuels and green energy, especially bio-ethanol, which is derived from a range of agricultural products, it is not surprising that there is a topical and developing literature on the spillovers between energy and agricultural markets. Modelling and testing spillovers between the energy and agricultural markets has typically been based on estimating multivariate conditional volatility models, specifically the Baba, Engle, Kraft, and Kroner (BEKK) and dynamic conditional correlation (DCC) models. A serious technical deficiency is that the Quasi-Maximum Likelihood Estimates (QMLE) of a Full BEKK matrix, which is typically estimated in examining volatility spillover effects, has no asymptotic properties, except by assumption, so that no valid statistical test of volatility spillovers is possible. Some papers in the literature have used the DCC model to test for volatility spillovers. However, it is well known in the financial econometrics literature that the DCC model has no regularity conditions, and that the QMLE of the parameters of DCC has no asymptotic properties, so that there is no valid statistical testing of volatility spillovers. The purpose of the paper is to evaluate the theory and practice in testing for volatility spillovers between energy and agricultural markets using the multivariate Full BEKK and DCC models, and to make recommendations as to how such spillovers might be tested using valid statistical techniques. Three new definitions of volatility and covolatility spillovers are given, and the different models used in empirical applications are evaluated in terms of the new definitions and statistical criteria.