Successive Generations Research Articles

Experimental Evolution Induced by Maternal Post-copulatory Factors in Drosophila.

Experimental evolution is a powerful approach to study the mechanisms underlying the adaptation of selected characters under the conditions chosen in the laboratory. Drosophila melanogaster is a species frequently used to investigate the experimental evolution of characters, especially those related to reproduction. Recent intra-generational studies showed that cis-vaccenyl acetate (cVa), a sex pheromone transferred with bacteria on eggs by females either 1day (D1) or 5days (D5) after copulation, differentially affected the behavior and pheromone release in adult males emerging from these eggs. Here, we extended this finding to determine whether this alternative egg exposure repeated over many generations could affect a larger set of reproduction-related characters in both sexes. To test the repetitive effects of maternal D1 or D5 post-copulatory factors, we carried out an experimental selection procedure consisting of exposing eggs during 40 successive generations to D1 or D5 maternal post-copulatory factors. We compared cVa and cuticular pheromones, courtship and mating behaviors, and fecundity at different generations in flies of D1 and D5 lines. Based on findings obtained at earlier generations, we also determined survival, bacterial composition and gene expression in adults. Some of these complex traits significantly diverged between D1 and D5 lines indicating that maternal post-copulatory factors transmitted to eggs can influence adult life history traits.

Generation of viable hypomorphic and null mutant plants via CRISPR-Cas9 targeting mRNA splicing sites.

Genetic analysis is important for modern plant molecular biology, and in this regard, the existence of specific mutants is crucial. While genome editing technologies, particularly CRISPR-Cas9, have revolutionized plant molecular biology by enabling precise gene disruption, knockout methods are ineffective for lethal genes, necessitating alternatives like gene knockdown. This study demonstrates the practical generation of a hypomorphic mutant allele, alongside severe null mutant alleles, via the targeting of mRNA splicing sites using CRISPR-Cas9. The Arabidopsis HIGH PLOIDY 2 (HPY2) encodes a yeast NSE2 ortholog, part of the conserved eukaryotic SMC5/6 complex, with SUMO E3 ligase activity essential for cell cycle progression and plant development. Loss-of-function HPY2 mutants exhibit severe dwarfism and seedling lethality, making functional analysis challenging. To overcome these limitations, we created HPY2 knockdown mutants as novel tools to investigate gene function. Of the three mutant alleles, the hpy2-cr1 and hpy2-cr2 mutants resembled the existing severe hpy2-1 allele, both harboring a single base pair insertion in one exon, causing significant root shortening and seedling lethality. In contrast, the hypomorphic mutant hpy2-cr3, which has a five bp deletion at an intron-exon junction, showed relatively longer root growth and survived until the reproductive stage. RT-PCR analysis of hpy2-cr3 revealed atypical mRNAs producing truncated polypeptides that retained some HPY2 function, explaining the milder phenotype. These results establish the successful generation of novel hypomorphic mutant alleles critical for studying the lethal gene HPY2, and demonstrate the usefulness of CRISPR-Cas9 for producing viable hypomorphic mutants for investigating complex genetic interactions.

Wild again: recovery of a beneficial Cannabis seed endophyte from low domestication genotypes

BackgroundBeyond carrying the plant embryo, seeds harbour intricate microbial communities whose transmission across successive plant generations can significantly influence the ecological and evolutionary dynamics of plant–microbe symbioses. The process of plant domestication has potential repercussions in genes involved in plant-microbiome interactions. However, the extent to which breeding can impact the seed microbiome is sparsely explored. Cannabis is a high-value crop but sparsely subjected to agricultural innovations established in other crop species during the last century. Here, we conduct a large-scale analysis of the bacterial seed microbiome of Cannabis across different domestication grades and investigate the potential of seed-associated endophytes as plant growth-promoting agents under both controlled and field conditions.ResultsAnalysis of Cannabis seed endophyte composition and diversity across 46 plant genotypes revealed 813 different bacterial genera with a predominance of Gammaproteobacteria, Bacilli, Actinobacteria and Alphaproteobacteria but a genotype-specific microbiome. The assessment of domestication and breeding on microbial assembly revealed a higher bacterial diversity in low domestication genotypes (Shannon index, H′: 1.21 vs. 1.05) and a higher homogeneity in bacterial composition caused by line development. Further, a seed bacterial isolate (Bacillus frigoritolerans C1141) associated with low domestication genotypes, and with genes associated with bio-fertilization, bioremediation and phytohormone production, increased plant growth by 42.3% at the time of harvest, under field conditions.ConclusionThis study addresses critical knowledge gaps related to the assembly of the Cannabis seed-endophytic microbiome. It reveals that Cannabis breeding is linked to alterations of seed microbial communities, which potentially led to the loss of bacteria with functional significance. These results highlight the importance of preserving seed microbiomes in plant breeding to support sustainable plant health and growth enhancement in Cannabis.CAHvc7HPtw2foEoMit4yw-Video

Strategic insights into the cultivation of pancreatic cancer organoids from endoscopic ultrasonography-guided biopsy tissue

BACKGROUND The frequent suboptimal efficacy of endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) to culture pancreatic cancer (PC) organoids (PCOs) poses a major challenge in the advancement of personalized medicine for advanced PC. AIM To explore how to obtain appropriate puncture tissues from EUS-FNB and optimize the strategy for efficiently constructing PCOs, providing an efficient tool for the advancement of personalized medicine. METHODS Patients who underwent EUS-FNB for the diagnosis of PC tissue were prospectively enrolled. We refined the endoscopic biopsy procedures and organoid cultivation techniques. All tissue specimens verified by on-site pathological assessment were cultured in a semi-suspended medium in a microfluidic environment. We assessed differences in PCOs cultured beyond and below five generations examining patient demographics, specimen and organoid attributes, and the sensitivity of organoids to a panel of clinical drugs through cell viability assays. RESULTS In this study, 16 patients with PC were recruited, one sample was excluded because onsite cytopathology showed no tumor cells. Successful organoid generation occurred in 93.3% (14 of 15) of the EUS-FNB specimens, with 60% (9 of 15) sustaining over five generations. Among these patients, those with a history of diabetes, familial cancer, or larger tumors exhibited enhanced PCO expandability. The key factors influencing long-term PCOs expansion included initial needle sample quality (P = 0.005), rapid initiation of organoid culture post-isolation (P ≤ 0.001), and high organoid activity (P = 0.031). Drug sensitivity analysis revealed a partial response in two patients following therapeutic intervention and surgery and stable disease in four patients, indicating a moderate correlation between organoid response and clinical outcomes. CONCLUSION Optimal initial needle sampling, rapid and precise biopsy sample processing, process isolated samples as soon as possible, and sufficient cellular material are crucial for successful cultivating PCOs. High organoid activity is an important factor in maintaining their long-term expansion, which is essential for shortening the time of drug sensitivity analysis and is the basis of PC research.

Targeted engineering of camelina and pennycress seeds for ultrahigh accumulation of acetyl-TAG

Acetyl-TAG (3-acetyl-1,2-diacylglycerol), unique triacylglycerols (TAG) possessing an acetate group at the sn-3 position, exhibit valuable properties, such as reduced viscosity and freezing points. Previous attempts to engineer acetyl-TAG production in oilseed crops did not achieve the high levels found in naturally producing Euonymus seeds. Here, we demonstrate the successful generation of camelina and pennycress transgenic lines accumulating nearly pure acetyl-TAG at 93 mol% and 98 mol%, respectively. These ultrahigh acetyl-TAG synthesizing lines were created using gene-edited FATTY ACID ELONGASE1 (FAE1) mutant lines as an improved genetic background to increase levels of acetyl-CoA available for acetyl-TAG synthesis mediated by the expression of EfDAcT, a high-activity diacylglycerol acetyltransferase isolated from Euonymus fortunei. Combining EfDAcT expression with suppression of the competing TAG-synthesizing enzyme DGAT1 further enhanced acetyl-TAG accumulation. These ultrahigh levels of acetyl-TAG exceed those in earlier engineered oilseeds and are equivalent or greater than those in Euonymus seeds. Imaging of lipid localization in transgenic seeds revealed that the low amounts of residual TAG were mostly confined to the embryonic axis. Similar spatial distributions of specific TAG and acetyl-TAG molecular species, as well as their probable diacylglycerol (DAG) precursors, provide additional evidence that acetyl-TAG and TAG are both synthesized from the same tissue-specific DAG pools. Remarkably, this ultrahigh production of acetyl-TAG in transgenic seeds exhibited minimal negative effects on seed properties, highlighting the potential for production of designer oils required for economical biofuel industries.

Deep learning-driven super-resolution in Raman hyperspectral imaging: Efficient high-resolution reconstruction from low-resolution data

Deep learning (DL) has become an indispensable tool in hyperspectral data analysis, automatically extracting valuable features from complex, high-dimensional datasets. Super-resolution reconstruction, an essential aspect of hyperspectral data, involves enhancing spatial resolution, particularly relevant to low-resolution hyperspectral data. Yet, the pursuit of super-resolution in hyperspectral analysis is fraught with challenges, including acquiring ground truth high-resolution data for training, generalization, and scalability. The pressing issue of extended spectral acquisition times, notably for high-resolution scans, is a significant roadblock in hyperspectral imaging. Super-resolution methods offer a promising solution by providing higher spatial resolution data to expedite data collection and yield more efficient outcomes. This paper delves into a practical application of these concepts using Raman imaging, where spectral acquisition times can be prohibitively long. In this context, DL-based super-resolution models demonstrate their efficacy by predicting and reconstructing high-resolution Raman data from low-resolution input, eliminating the need for resource-intensive high-resolution scans. While previous work often relied on substantial high-resolution datasets, this study showcases the ability to achieve similar outcomes even with limited data, presenting a more practical and cost-effective approach. The results offer a glimpse into the transformative potential of this technology to streamline hyperspectral imaging applications by saving valuable time and resources through the successful generation of high-resolution data from low-resolution inputs.

HOST COUNTRY LANGUAGE ACQUISITION AMONG FIRST-GENERATION YAGLIDERE IMMIGRANTS IN THE USA AND THE MAINTENANCE OF THE TURKISH LANGUAGE IN SUCCESSIVE GENERATIONS VIA SOCIAL NETWORKS

This article investigated the effect of the social networks of Yaglidere Turkish immigrants on language acquisition and the maintenance of heritage languages by successive generations in the USA. The study was conducted in the cities of Patterson and Burlington between January 2018 and July 2018. This research used qualitative research methods to analyze ethnographic interviews and participant observations. Data were collected using participant observation and informal talks with immigrants conducted in different informal settings such as participants’ houses, their restaurants, and other cafes in Burlington and Paterson. The interviews lasted from 40 to 90 minutes. Questions were open-ended and focused on the role of social networks in the acquisition of English language skills. In order to analyze the resulting data, the audio recordings were transcribed and translated into English. The interviews were first transcribed into Microsoft Word files and then imported into Maxqda, a software program for qualitative analysis, where the data were coded for study. The results indicated that even though social networks have destructive effects among first-generation immigrants, they have undeniable constructive effects on language maintenance in other generations. So, what is destructive for the first generation turns into constructive for the other generations.

Emergence of dauer larvae in Caenorhabditis elegans disrupts continuity of host-microbiome interactions.

Nematodes are common in most terrestrial environments, where populations are often known to undergo cycles of boom and bust. Useful in such scenarios, nematodes present developmental programs of diapause, giving rise to stress-resistant larvae and enabling dispersal in search of new resources. Best studied in Caenorhabditis elegans, stress resistant dauer larvae emerge under adverse conditions, primarily starvation, and migrate to new niches where they can resume development and reproduce. C. elegans is a bacterivore but has been shown to harbor a persistent and characteristic gut microbiome. While much is known about the gut microbiome of reproducing C. elegans, what dauers harbor is yet unknown. This is of interest, as dauers are those that would enable transmission of microbes between nematode generations and geographical sites, maintaining continuity of host-microbe interactions. Using culture-dependent as well as sequencing-based approaches we examined the gut microbiomes of dauers emerging following population growth on ten different natural-like microbially diverse environments as well as on two defined communities of known gut commensals and found that dauers were largely devoid of gut bacteria. These results suggest that host gut-microbiome interactions in C. elegans are not continuous across successive generations and may reduce the likelihood of long-term worm-microbe coevolution.

Virus-Induced Gene Silencing Simultaneously Exploits ‘Attract and Kill’ Traits in Plants and Insects to Manage Huanglongbing

Abstract The vector-borne disease Huanglongbing (HLB) causes severe economic losses to citrus production worldwide with no available cure. Herein, we applied virus-induced gene silencing technology to engineer citrus that preferentially attracted and specifically killed Diaphorina citri, the vector associated with HLB. We engineered the infectious citrus tristeza virus (CTV-T36) clone to carry three truncated genes. The triple construct (CTV-tAwd-tWnt-tPDS) produces small interfering RNAs (siRNAs) against phytoene desaturase, PDS, to yield a phenotype with visual, olfactory, and gustatory cues that preferentially attracted D. citri. In addition, siRNAs targeted two genes related to flight in D. citri, abnormal wing disc (DcAwd) and wingless (DcWnt), that caused wing malformations and decreased survival in psyllids that fed on plants inoculated with the engineered virus. During two successive generations, D. citri reared on CTV-tAwd-tWnt-tPDS-inoculated plants exhibited higher mortality across life stages as well as reduced fecundity and fertility as compared with those reared on non-infected plants or CTV-wt-inoculated plants. Furthermore, CTV-tAwd-tWnt-tPDS-inoculated plants shortened the lifespan of D. citri by more than 20 days. Morphological abnormalities were noted in those adults that did successfully emerge on plants inoculated with CTV-tAwd-tWnt-tPDS, including cocked wings with a bowl-shaped depression and/or a convex shape. Phloem sap from CTV-tAwd-tWnt-tPDS-inoculated plants decreased the survival of D. citri adults, confirming that siRNAs were present in the sap of these plants. Collectively, we provide proof of concept for a novel variant of the attract-and-kill method where the cultivated crop is potentially transformed into a hyper-attractive population and transmission sink for a phytopathogen vector.

Nano-priming of Vigna radiata seeds with opuntia stricta-derived γFe2O3 nanoparticles

The experimental investigation aimed to enhance sustainable and biocompatible nano-agriculture by examining the possible effects of biosynthesized nanoparticles (γFe2O3 NPs) on seed growth and growth parameters of Vigna radiata. The outcomes of various characterization procedures such as FTIR, XRD, UV, and Fe-SEM were used to determine the successful generation of γFe2O3 NPs (nanoparticles), which were capped with multiple phytoconstituents contained in the Opuntia stricta extract. γFe2O3 NPs were synthesised, as evidenced by the peak's presence, having a mean crystallite size of 13.9 nm, and were successfully detected using X-ray diffraction (XRD). Crucial Energy Dispersive X-ray Spectroscopy (EDS) testing also yielded unambiguous proof of the element iron's presence. Raman spectroscopy was used to confirm the synthesis of pure maghemite nanoparticles. Wide areas around 350, 500, 670, and 1330 cm-1 values verify the creation of pure maghemite. TGA analysis was performed to check the stability of nanoparticles in which the residual weight was found to be 87.62%. TEM images confirm the spherical shape, and the mean size of the nanoparticles was found to be 12.28 nm. Through a number of tests, the analysis showed that the nanoparticles have a strong antioxidant capacity. This experiment aimed to determine how biogenic γFe2O3 Nanoparticles affected Vigna radiata seed germination. Measurements of shoot and root lengths, seed vigour index, germination rates, mean daily germination, and peak value (PV) were all included of the assessment. There was a total of four distinct γFe2O3 NPs concentrations examined (25, 50, 75, and 100 μg/mL). The penetration of the γFe2O3 NPs affects the germination and growth of the Vigna radiata seeds. When compared to untreated seeds, the germination index values for Vigna radiata seeds that underwent effective treatment with γFe2O3 NPs significantly improved.

Belief Formation: A Cultural Evolutionary Lens

This paper investigates changes in belief and their evolution in relation to the paradigm of cultural evolution. It underlines the interaction of the environmental factor with the social dynamic. The model proposed herein is extremely widespread and involves the creation, maintenance, and diffusion of beliefs that afford a perspective on how such processes influence individual and collective psychological constructs. By synthesizing theories in the fields of biology, anthropology, and psychology, this research will argue that cultural evolution is one key mechanism able to explain both diversity and variability in human belief. The examination suggests that beliefs cannot be cast solely as some sort of passive variant of personal cognition; instead, they are actively generated by cultural dynamics and social learning techniques such as imitation and instruction. It is a book that places more emphasis on the role of political ideology in accepting scientific evidence and shows how directed reasoning leads to the perpetuation of noxious beliefs. It then investigates transfer biases supporting the reproduction of cultural traits across successive generations, hence affecting social structure and any effort of cooperation. This may lead to a nuanced grasp of how beliefs can be advantageous or disastrous, considering the prevailing social structures and ecology within which they live. Based on the wealth of research regarding under what circumstances beliefs arise and spread, this paper examines from a critical perspective psychological processes of belief systems and what they might portend for human behavior and social organization.

Kangaku and the State: Colonial Collaboration between Korean and Japanese Traditional Sinologists

This article examines the response of kangaku 漢学, or traditional sinological study, to modernity in Japan and colonial Korea by focusing on institutionalization and the interactions between scholars of traditional sinology in Japan and colonized Korea. In the Japanese Empire, kangaku actively demonstrated that it could contribute to the nation-state and became a part of the modern educational system, including the Imperial University. The favorable atmosphere toward kangaku in the Japanese Empire also enabled the institutionalization of kangaku in colonial Korea. The process of institutionalization there was deeply influenced by the traditional network of Japanese sinologists. Traditional sinologists in Japan and colonial Korea were able to cooperate based on a shared “shibun (斯文 “This Culture of Ours”) consciousness,” a kind of consciousness of crisis that originated in the Analects. The shibun consciousness was rooted in the traditional literary world, where borders and contemporaneity were relatively ambiguous. Within the university system, kangaku gradually faced the pressure of specialization and elaboration of modern scholarship and the demands of the nation-state. Thus, successive generations of Korean and Japanese sinologists moved toward a new modern ideology that went beyond “shibun consciousness.”

Resistance risk and mechanism of Ustilaginoidea virens to pydiflumetofen

Rice false smut, caused by Ustilaginoidea virens, is a devastating fungal disease in rice that not only leads to yield reduction but also poses a serious threat to food safety and human health due to the production of numerous mycotoxins. Pydiflumetofen, one of the most promising SDHI fungicides widely used for controlling various plant diseases, lacks available information regarding its antifungal activity against U. virens and the potential risk of resistance development in this pathogen. In this study, we evaluated the sensitivity of 33 field-isolated strains of U. virens to pydiflumetofen using mycelial growth inhibition method and assessed the potential for resistance development. The EC50 values for pydiflumetofen against the tested strains ranged from 0.0032 to 0.0123 μg/mL, with an average EC50 value of 0.0056 ± 0.0025 μg/mL. In addition, four strains of U. virens were randomly selected for chemical taming to evaluate their resistance risk to pydiflumetofen, resulting in the successful generation of eight stable and inheritable resistant mutants at a frequency of 1 %. These mutants exhibited significant differences in biological fitness compared to their respective parental strains. Cross-resistance tests revealed a correlation between pydiflumetofen and fluxapyroxad as well as fluopyram, but no evidence of cross-resistance was observed between pydiflumetofen and boscalid or tebuconazole. Therefore, we can conclude that the risk of resistance development in U. virens to pydiflumetofen is moderate. Finally, the target genes SDHB, SDHC, and SDHD in U. virens were initially identified, cloned, and sequenced to elucidate the mechanism underlying U. virens resistance to pydiflumetofen. Three mutation genotypes were found in the mutants: SDHB-H239Y, SDHB-H239L, and SDHC-A77V. The mutants carrying SDHB-H239Y exhibited low resistance, while SDHC-A77V showed moderate resistance, but the mutants with SDHB-H239L demonstrated high resistance. These findings contribute significantly to our comprehensive understanding of molecular mechanisms involved in the resistance of U. virens to pydiflumetofen, and provide an important reference for chemical control strategies against rice false smut in the field.

Antibody Modification via Lipoic Acid Ligase A-Mediated Site-Specific Labeling.

Enzymatic modification, particularly utilizing lipoic acid ligase (LplA), has emerged as a transformative approach in biopharmaceuticals, enabling precise and site-specific protein modifications. This review delves into the innovative applications of LplA in antibody modifications, including the creation of antibody-drug conjugates (ADCs) and the advancement of tag-free conjugation techniques. LplA's ability to facilitate the incorporation of bioorthogonal groups and its adaptability to various substrates underscores its versatility. Key developments include the successful generation of dual-labeled antibodies and the application of LplA in modifying antibody fragments. Additionally, the review explores the potential for LplA to enhance the therapeutic efficacy of ADCs through improved drug-to-antibody ratios and site-specific payload attachment. The implications of these advancements are significant, suggesting that LplA-mediated modifications could lead to more effective and targeted antibody-based therapies. This review aims to provide a comprehensive overview of LplA's role in expanding the possibilities of enzymatic conjugation, setting the stage for future research and clinical applications.

Frontiers in CAR-T Cell Therapy: Current Applications and Future Directions

CAR-T cell therapy, an ascending star in the immunotherapy landscape, harnesses the patient's innate immune defenses to confront cancer and a spectrum of hematologic disorders, while also exhibiting promising avenues for application in other maladies. This comprehensive review delves into the fundamental mechanisms of CAR-T cell therapy, the evolution and design strategies of successive generations of CAR-T cells, as well as the advancements and clinical implementations achieved in treating a diverse array of diseases.

Analysis of the winter oilseed rape recombination landscape suggests maternal-paternal bias.

Recombination, the reciprocal exchange of DNA between homologous chromosomes, is a mandatory step necessary for meiosis progression. Crossovers between homologous chromosomes generate new combinations of alleles and maintain genetic diversity. Due to genetic, epigenetic, and environmental factors, the recombination landscape is highly heterogeneous along the chromosomes and it also differs between populations and between sexes. Here, we investigated recombination characteristics across the 19 chromosomes of the model allopolyploid crop species oilseed rape (Brassica napus L.), using two unique multiparental populations derived from two genetically divergent founder pools, each of which comprised 50 genetically diverse founder accessions. A fully balanced, pairwise chain-crossing scheme was utilized to create each of the two populations. A total of 3213 individuals, spanning five successive generations, were genotyped using a 15K SNP array. We observed uneven distribution of recombination along chromosomes, with some genomic regions undergoing substantially more frequent recombination in both populations. In both populations, maternal recombination events were more frequent than paternal recombination. This study provides unique insight into the recombination landscape at chromosomal level and reveals a maternal-paternal bias for recombination number with implications for breeding.

Sonochemical preparation of powerful S-scheme Zr(HPO4)2/g-C3N4 heterojunction for photocatalytic degradation of rhodamine B under natural solar radiations

An effective Zr(HPO4)2/g-C3N4 S-scheme heterojunction was synthesized by sonochemical coupling of Zr(HPO4)2 nanoparticles as an oxidative photocatalyst [EVB = +3.0 eV] with g-C3N4 nanosheets as an effective reductive photocatalyst [ECB = −1.25 eV] for photocatalytic degradation of rhodamine B dye under natural solar radiation of 1000 W power. The physicochemical properties of the as-synthesized heterojunctions were investigated by X-ray diffraction [XRD], N2-adsorption-desorption isotherm, diffuse reflectance spectrum [DRS], photoluminescence [PL], scanning electron microscope [SEM], X-ray photoelectron spectroscope [XPS], and high resolution transmission electron microscope [HRTEM]. The experimental results implied the agglomeration of Zr(HPO4)2 nanoparticles on g-C3N4 sheets which reduced the specific surface area of the solid specimen from 88 to 21 m2/g. The significant increase in the photocatalytic degradation rate of RhB dye with introducing Zr(HPO4)2 nanoparticles implied that Zr(HPO4)2 plays a crucial role in reducing the band gap energy and remarkable increasing in the rate of electron-hole separation. The photocatalytic experiments implied that incorporation of 5 wt% Zr(HPO4)2 on g-C3N4 sheets destroyed 98 % of RhB dye during 3 h of light illumination with pseudo-first-order rate of 0.048 min−1. The remarkable enhancement in the photocatalytic performance of Zr(HPO4)2/g-C3N4 heterojunctions was ascribed to successful generation of an effective S-scheme heterojunction with strong redox power, utilizing of both hydroxyl and superoxide radicals in the degradation process and limiting the electron-hole recombination rate. Based on scavenger experiments and terephthalic acid PL analysis, the S-scheme pathway was chosen as the proposed mechanism for photocatalytic charge transfer. The as-synthesized Zr(HPO4)2/g-C3N4 heterojunction with exceptional redox power is considered a novel candidate for destructing organic pollutants that exist in industrial wastewater.

Neutronics Analysis on High-Temperature Gas-Cooled Pebble Bed Reactors by Coupling Monte Carlo Method and Discrete Element Method

The High-Temperature Gas-Cooled Pebble Bed Reactor (HTG-PBR) is notable in the advanced reactor realm for its online refueling capabilities and inherent safety features. However, the multiphysics coupling nature of HTG-PBR, involving neutronic analysis, pebble flow movement, and thermo-fluid dynamics, creates significant challenges for its development, optimization, and safety analysis. This study focuses on the high-fidelity neutronic modelling and analysis of HTG-PBR with an emphasis on achieving an equilibrium state of the reactor for long-term operations. Computational approaches are developed to perform high-fidelity neutronics analysis by coupling the superior modelling capacities of the Monte Carlo Method (MCM) and Discrete Element Method (DEM). The MCM-based code OpenMC and the DEM-based code LIGGGHTS are employed to simulate the neutron transport and pebble movement phenomena in the reactor, respectively. To improve the computational efficiency to expedite the equilibrium core search process, the reactor core is discretized by grouping pebbles in axial and radial directions with the incorporation of the pebble position information from DEM simulations. The OpenMC model is modified to integrate fuel circulation and fresh fuel loading. All of these measures ultimately contribute to a successful generation of an equilibrium core for HTG-PBR. For demonstration, X-energy’s Xe-100 reactor—a 165 MW thermal power HTG-PBR—is used as the model reactor in this study. Starting with a reactor core loaded with all fresh pebbles, the equilibrium core search process indicates the continuous loading of fresh fuel is required to sustain the reactor operation after 1000 days of fuel depletion with depleted fuel circulation. Additionally, the model predicts 213 fresh pebbles are needed to add to the top layer of the reactor to ensure the keff does not reduce below the assumed reactivity limit of 1.01.

Safety Aspects of Sodium-Ion Batteries: Prospective Analysis from First Generation Towards More Advanced Systems

After an introductory reminder of safety concerns pertaining to early rechargeable battery technologies, this review discusses current understandings and challenges of advanced sodium-ion batteries. Sodium-ion technology is now being marketed by industrial promoters who are advocating its workable capacity, as well as its use of readily accessible and cheaper key cell components. Often claimed to be safer than lithium-ion cells, currently only limited scientifically sound safety assessments of sodium-ion cells have been performed. However, the predicted sodium-ion development roadmap reveals that significant variants of sodium-ion batteries have entered or will potentially enter the market soon. With recent experiences of lithium-ion battery failures, sodium-ion battery safety management will constitute a key aspect of successful market penetration. As such, this review discusses the safety issues of sodium-ion batteries, presenting a twofold innovative perspective: (i) in terms of comparison with the parent lithium-ion technology making use of the same working principle and similar flammable non-aqueous solvent basis, and (ii) anticipating the arrival of innovative sub-chemistries at least partially inspired from successive generations of lithium-ion cells. The authors hope that the analysis provided will assist concerned stakeholders in the quest for safe marketing of sodium-ion batteries.

A History of Polymyalgia Rheumatica: A Narrative Review.

Polymyalgia rheumatica (PMR) is characterised by stiffness and pain in the shoulders, hips, and neck and presents most commonly in the eighth decade. It can coexist with giant cell arteritis and the two diseases may share some pathophysiological mechanisms. This narrative review considers present-day ideas about PMR in a historical context, from the first names and descriptions of this disease entity, via successive generations of classification criteria sets, and finally to implications for clinical diagnosis. The characteristic distribution of musculoskeletal inflammation in PMR, and its relationship to vasculitic and synovitic diseases, have framed the way that PMR is described, classified, diagnosed and treated. A response to glucocorticoids is not specific to PMR and so it is important for rheumatologists to support general practitioners in making a definite diagnosis. Multi-stakeholder collaboration will improve current pathways for fast, accurate diagnosis and safe and effective treatment.