Study on the risk identification of abnormal gas outbursts based on the mechanism of biological immunity

With the depletion of shallow coal resources, mining is gradually extending to deeper levels, with increasing gas content and gas pressure. Aabnormal gas outbursts phenomena occurs from time to time, posing a serious threat to coal mine safety production. Therefore, the risk identification of abnormal gas outbursts is of urgent practical significance. However, the process of identifying abnormal gas outbursts risk imposes higher requirements on the ability of adaptability, self-learning, and self-organization. The artificial immune technology based on the biological immune mechanism provides a powerful information processing and problem-solving paradigm, showing certain advantages in dynamic risk identification, which can meet the needs of dynamic risk identification of abnormal gas outbursts. In order to achieve dynamic risk identification of abnormal gas outbursts under complex underground conditions, provide decision-making basis for rapid warning and early prevention of abnormal gas outbursts, the principles of immune recognition of biological immune systems were adopted. Research was conducted on the identification of spatial risk zones for abnormal gas outbursts, the adaptive recognition algorithm based on T-B cell principles, and the type recognition of abnormal gas outbursts based on the Dynamic Time Warping algorithm. A risk identification model for abnormal gas outbursts based on the biological immune mechanism was constructed and tested in the 9111 mining face of a mine in Huaibei. The results show: (1) The adaptive recognition algorithm based on T-B cell principles can adaptively recognize the characteristic vectors of abnormal gas outbursts by adaptive adjustment of detectors and cloning and mutation of learning vectors, achieving the recognition and memorization of known or unknown feature vectors under dynamically changing environmental conditions. (2) The adaptive recognition algorithm for abnormal gas outbursts based on T-B cell principles and the type recognition algorithm for abnormal gas outbursts based on the Dynamic Time Warping algorithm, combined with the characteristics of biological immune systems, construct a risk identification model for abnormal gas outbursts based on the biological immune mechanism, which has the characteristics of adaptability, learning, and memorization. (3) Taking a abnormal gas outburst event in a certain 9111 working face of a mine in Huaibei as an example, the model was verified by inputting the characteristic vectors of abnormal gas outbursts and the output of the risk identification of abnormal gas outbursts based on the biological immune mechanism. The research results show that the dynamic risk identification model for abnormal gas outbursts based on the biological immune mechanism can meet the requirements of problem-solving in constantly changing complex environments, achieve dynamic risk identification of abnormal gas outbursts, and provide a basis for risk warning and intelligent decision-making for abnormal gas outbursts in mines.

The eusocial non-code: Unveiling the impact of noncoding RNAs on Hymenoptera eusocial evolution

Eusociality, characterized by reproductive division of labor, cooperative brood care, and multi-generational cohabitation, represents a pinnacle of complex social evolution, most notably manifested within the Hymenoptera order including bees, ants, and wasps. The molecular underpinnings underlying these sophisticated social structures remain an enigma, with noncoding RNAs (ncRNAs) emerging as crucial regulatory players. This article delves into the roles of ncRNAs in exerting epigenetic control during the development and maintenance of Hymenopteran eusociality. We consolidate current findings on various classes of ncRNAs, underscoring their influence on gene expression regulation pertinent to caste differentiation, developmental plasticity, and behavioral modulation. Evidence is explored supporting the hypothesis that ncRNAs contribute to epigenetic landscapes fostering eusocial traits through genomic regulation. They are likely to play an important role in eusociality "point of no return". Critical analysis is provided on the functional insights garnered from ncRNA profiles correlated with caste-specific phenotypes, specifical for phylogenetic branches and transitional sociality models, drawing from comparative genomics and transcriptomics studies. Overall, ncRNA provides a missed understanding of both "genetic toolkit" and "unique genes" hypotheses of eusociality development. Moreover, it points to gaps in current knowledge, advocating for integrative approaches combining genomics, proteomics, and epigenetics to decipher the complexity of eusociality. Understanding the ncRNA contributions offers not only a window into the molecular intricacies of Hymenoptera sociality but also extends our comprehension of how complex biological systems evolve and function.

Social organization of necrophoresis: insights into disease risk management in ant societies

Insect societies, which are at a high risk of disease outbreaks, have evolved sanitary strategies that contribute to their social immunity. Here, we investigated in the red ant Myrmica rubra, how the discarding of nestmate cadavers is socially organized depending on the associated pathogenicity. We examined whether necrophoresis is carried out by a specific functional group of workers or by any nestmates that may become short-term specialists. By observing the behavioural profiles of tagged individuals, we assigned half of the colony members to functional groups (foragers, intermittent-foragers, domestics, nurses and inactives). Following the introduction of uninfected or sporulating corpses into the nest, intermittent-foragers were the functional group most involved in necrophoresis, as they touched, moved and discarded more cadavers. Interestingly, sporulating corpses induced a more generalized response in workers from all functional groups, thereby accelerating their rejection from the nest. The individuals contacting corpses were also prophylactically engaged in more grooming behaviour, suggesting the existence of hygienist workers within ant colonies. These findings raise questions about a trade-off existing between concentrating health risks on a few workers who are highly specialized in necrophoresis and exposing a larger population of nestmates who cooperate to speed up nest sanitization.

Exploring immune memory traits in the social immunity of a fungus-growing ant

The immune system is crucial for organisms to defend against pathogens. Likewise, analogous immune features evolved against similar pressures at the superorganism scale. Upregulating hygiene to the same fungus pathogen is one assumption for convergent immune mechanisms in social insects, although more evidence of immune memory features remains to be confirmed. Here, we assess immune memory traits at the colony level in the leaf-cutting ant Atta sexdens. We exposed their fungus cultivar to both homologous and heterologous challenges with the entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana, as well as the mycoantagonistic fungi Fusarium oxysporum and Trichoderma spirale. By measuring ants' behaviours, we evaluated the capacity of A. sexdens: (i) to enhance their collective hygiene, (ii) speed their hygiene in further infections, (iii) how long this capacity lasts in the colonies and (iv) the degree of specificity to increase hygienic responses. Fungus grooming behaviour was enhanced mostly against entomopathogenic fungi, with a trend of faster reactions during homologous challenges. In general, the capacity to elicit such upregulated actions lasted for up to 30 days, but no longer than 60 days. Overall, colonies exhibited a degree of immune specificity, enhancing hygiene only in response to homologous exposures but decreasing it when infected secondarily with a different fungus, indicating flexible social immunity of A. sexdens after immune challenges.

Unconditional versus condition-dependent social immunity

Socially living animals can counteract disease through cooperative defences, leading to social immunity that collectively exceeds the sum of individual defences. In superorganismal colonies of social insects with permanent caste separation between reproductive queen(s) and nonreproducing workers, workers are obligate altruists and thus engage in unconditional social immunity, including highly specialised and self-sacrificial hygiene behaviours. Contrastingly, cooperation is facultative in cooperatively breeding families, where all members are reproductively totipotent but offspring transiently forgo reproduction to help their parents rear more siblings. Here, helpers should either express condition-dependent social immunity or disperse to pursue independent reproduction. We advocate inclusive fitness theory as a framework to predict when and how indirect fitness gains may outweigh direct fitness costs, thus favouring conditional social immunity.

Major changes in domain arrangements are associated with the evolution of termites

Domains as functional protein units and their rearrangements along the phylogeny can shed light on the functional changes of proteomes associated with the evolution of complex traits like eusociality. This complex trait is associated with sterile soldiers and workers, and long-lived, highly fecund reproductives. Unlike in Hymenoptera (ants, bees, and wasps), the evolution of eusociality within Blattodea, where termites evolved from within cockroaches, was accompanied by a reduction in proteome size, raising the question of whether functional novelty was achieved with existing rather than novel proteins. To address this, we investigated the role of domain rearrangements during the evolution of termite eusociality. Analysing domain rearrangements in the proteomes of three solitary cockroaches and five eusocial termites, we inferred more than 5,000 rearrangements over the phylogeny of Blattodea. The 90 novel domain arrangements that emerged at the origin of termites were enriched for several functions related to longevity, such as protein homeostasis, DNA repair, mitochondrial activity, and nutrient sensing. Many domain rearrangements were related to changes in developmental pathways, important for the emergence of novel castes. Along with the elaboration of social complexity, including permanently sterile workers and larger, foraging colonies, we found 110 further domain arrangements with functions related to protein glycosylation and ion transport. We found an enrichment of caste-biased expression and splicing within rearranged genes, highlighting their importance for the evolution of castes. Furthermore, we found increased levels of DNA methylation among rearranged compared to non-rearranged genes suggesting fundamental differences in their regulation. Our findings indicate the importance of domain rearrangements in the generation of functional novelty necessary for termite eusociality to evolve.

Defensive behavior is linked to altered surface chemistry following infection in a termite society

The care-kill response determines whether a sick individual will be treated or eliminated from an insect society, but little is known about the physiological underpinnings of this process. We exploited the stepwise infection dynamics of an entomopathogenic fungus in a termite to explore how care-kill transitions occur, and identify the chemical cues behind these shifts. We found collective responses towards pathogen-injected individuals to vary according to severity and timing of pathogen challenge, with elimination, via cannibalism, occurring sooner in response to a severe active infection. However, injection with inactivated fungal blastospores also resulted in increased albeit delayed cannibalism, even though it did not universally cause host death. This indicates that the decision to eliminate an individual is triggered before pathogen viability or terminal disease status has been established. We then compared the surface chemistry of differently challenged individuals, finding increased amounts of long-chained methyl-branched alkanes with similar branching patterns in individuals injected with both dead and viable fungal blastospores, with the latter showing the largest increase. This coincided with the highest amounts of observed cannibalism as well as signs of severe moribundity. Our study provides new mechanistic insight into the emergent collective behaviors involved in the disease defense of a termite society.

Conflict and conflict resolution in the major transitions

Conflict and conflict resolution have been argued to be fundamental to the major transitions in evolution. These were key events in life's history in which previously independently living individuals cooperatively formed a higher-level individual, such as a multicellular organism or eusocial colony. Conflict has its central role because, to proceed stably, the evolution of individuality in each major transition required within-individual conflict to be held in check. This review revisits the role of conflict and conflict resolution in the major transitions, addressing recent work arguing for a minor role. Inclusive fitness logic suggests that differences between the kin structures of clones and sexual families support the absence of conflict at the origin of multicellularity but, by contrast, suggest that key conflicts existed at the origin of eusociality. A principal example is conflict over replacing the founding queen (queen replacement). Following the origin of each transition, conflict remained important, because within-individual conflict potentially disrupts the attainment of maximal individuality (organismality) in the system. The conclusion is that conflict remains central to understanding the major transitions, essentially because conflict arises from differences in inclusive fitness optima while conflict resolution can help the system attain a high degree of coincidence of inclusive fitness interests.

Dynamic pathogen detection and social feedback shape collective hygiene in ants

Cooperative disease defense emerges as group-level collective behavior, yet how group members make the underlying individual decisions is poorly understood. Using garden ants and fungal pathogens as an experimental model, we derive the rules governing individual ant grooming choices and show how they produce colony-level hygiene. Time-resolved behavioral analysis, pathogen quantification, and probabilistic modeling reveal that ants increase grooming and preferentially target highly-infectious individuals when perceiving high pathogen load, but transiently suppress grooming after having been groomed by nestmates. Ants thus react to both, the infectivity of others and the social feedback they receive on their own contagiousness. While inferred solely from momentary ant decisions, these behavioral rules quantitatively predict hour-long experimental dynamics, and synergistically combine into efficient colony-wide pathogen removal. Our analyses show that noisy individual decisions based on only local, incomplete, yet dynamically-updated information on pathogen threat and social feedback can lead to potent collective disease defense.

Distinct and enhanced hygienic responses of a leaf-cutting ant toward repeated fungi exposures

Leaf-cutting ants and their fungal crops are a textbook example of a long-term obligatory mutualism. Many microbes continuously enter their nest containing the fungal cultivars, destabilizing the symbiosis and, in some cases, outcompeting the mutualistic partners. Preferably, the ant workers should distinguish between different microorganisms to respond according to their threat level and recurrence in the colony. To address these assumptions, we investigated how workers of Atta sexdens sanitize their fungal crop toward five different fungi commonly isolated from the fungus gardens: Escovopsis sp., Fusarium oxysporum, Metarhizium anisopliae, Trichoderma spirale, and Syncephalastrum sp. Also, to investigate the plasticity of these responses toward recurrences of these fungi, we exposed the colonies with each fungus three times fourteen days apart. As expected, intensities in sanitization differed according to the fungal species. Ants significantly groom their fungal crop more toward F. oxysporum, M. anisopliae, and Syncephalastrum sp. than toward Escovopsis sp. and T. spirale. Weeding, self-, and allogrooming were observed in less frequency than fungus grooming in all cases. Moreover, we detected a significant increase in the overall responses after repeated exposures for each fungus, except for Escovopsis sp. Our results indicate that A. sexdens workers are able to distinguish between different fungi and apply distinct responses to remove these from the fungus gardens. Our findings also suggest that successive exposures to the same antagonist increase hygiene, indicating plasticity of ant colonies' defenses to previously encountered pathogens.

Chemical cues in disease recognition and their immunomodulatory role in insects

Preventing infections is crucial for host fitness and many insects modify their behaviour upon sensing a contagion. We review chemical cues that mediate insect behaviour in response to parasites, and diseased or dead conspecifics. Considering the large diversity of behavioural disease defences described, surprisingly little is known about disease-associated cues that mediate them, especially their chemoreceptor and neuronal details. Interestingly, disease cues do not only modify host behaviour, but they could also play a direct role in immune system activation via neuroendocrine regulation, bypassing the need for risky immunological contact with the parasite. Such crosstalk is an exciting emerging research area in insect ecological immunology that should prove invaluable in studying host-parasite interactions by combining analytical methods from chemical ecology.

Evidence for reduced immune gene diversity and activity during the evolution of termites

The evolution of biological complexity is associated with the emergence of bespoke immune systems that maintain and protect organism integrity. Unlike the well-studied immune systems of cells and individuals, little is known about the origins of immunity during the transition to eusociality, a major evolutionary transition comparable to the evolution of multicellular organisms from single-celled ancestors. We aimed to tackle this by characterizing the immune gene repertoire of 18 cockroach and termite species, spanning the spectrum of solitary, subsocial and eusocial lifestyles. We find that key transitions in termite sociality are correlated with immune gene family contractions. In cross-species comparisons of immune gene expression, we find evidence for a caste-specific social defence system in termites, which appears to operate at the expense of individual immune protection. Our study indicates that a major transition in organismal complexity may have entailed a fundamental reshaping of the immune system optimized for group over individual defence.