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Evolutionary game-based delegated proof of stake consensus for secure and efficient data storage in sensor networks
Get PDFWith the rapid expansion of sensor networks across domains such as environmental monitoring, industrial automation, and smart healthcare, ensuring secure and reliable data storage in resource-constrained environments has become a critical challenge. Traditional centralized storage systems struggle with data tampering, privacy leakage, and vulnerability to collusion among nodes. Blockchain technology, characterized by decentralization, immutability, and traceability, provides a promising foundation for trustworthy sensor data management. Among various consensus mechanisms, Delegated Proof of Stake (DPoS) has been recognized for its efficiency and low energy consumption, yet it faces two critical issues: limited incentives for ordinary sensor nodes to participate in voting and the risk of collusion that undermines fairness and stability. To overcome these limitations, this study proposes a blockchain-enabled sensor data storage framework incorporating a four-party evolutionary game model. The model explicitly captures the strategic interactions among cluster head nodes, ordinary sensor nodes, competing gateway nodes, and supervisory nodes, while integrating reputation evaluation, penalty enforcement, and supervisory oversight. Through evolutionary game analysis, the proposed framework reveals the stability conditions of node behaviors and identifies strategies that promote fair and secure consensus. Simulation results verify that the mechanism enhances node participation, suppresses collusion, accelerates consensus convergence, and achieves superior throughput and fault tolerance compared with existing schemes. This research provides theoretical insights and practical guidance for designing secure, efficient, and scalable blockchain-enabled sensor network data storage systems
Using in vitro models to ascertain whether multi-probiotic supplementation influences neurotransmitter and SCFA production in the absence of human cells
Get PDFAims
The present study aimed to explore microbial production of neurotransmitters related to cognitive function in the faecal microbiota of healthy older adults, and assess whether a multi-strain probiotic formula may influence production of these neuroactive metabolites, short-chain fatty acids, and the bacterial community.
Method and results
The current study employed a three-stage continuous culture system with faecal microbiota from three healthy older adult donors. Neuroactive compounds were quantified using liquid chromatography mass spectroscopy, SCFAs using gas chromatography, and the bacterial community was assessed using fluorescence in situ hybridization with flow cytometry and 16S rRNA sequencing. Addition of the probiotic supplement (Bifidobacterium lactis W51, Bifidobacterium lactis W52, Lactobacillus acidophilus W37, Lactobacillus salivarius W24, Lactobacillus casei W56, Bifidobacterium bifidum W23, Lactobacillus brevis W63, Lactococcus lactis W19, Lactococcus lactis W58) significantly increased the relative abundance of Lactococcus lactis in the transverse region, alongside a trend for increased Roseburia across the three colon regions modelled, valerate in the distal region, and GABA in the proximal region.
Conclusions
While administration of the probiotic only had a small effect of trending increases in the synthesis of GABA and valerate, this highlights important mechanisms by which probiotics could be involved in the gut-brain axis. The model also enabled the observation of limited microbial production of other neurotransmitters. Further exploration in human studies is therefore warranted. Probiotics were confirmed to lead to microbial changes, both directly (Lactococcus) and indirectly (Roseburia). This research helps to support mechanistic understanding of probiotics and the gut-brain axis
Water quality, heavy metal contamination, and ecological risk assessment in Asejire reservoir, Nigeria
Get PDFMonitoring water and sediment quality in freshwater ecosystems is essential for sustainable management and ecological protection. This study assessed heavy metal contamination in water and sediments from five sampling stations in Asejire Reservoir, Oyo State, Nigeria. A range of pollution indices was employed to quantify contamination levels. Principal Component Analysis (PCA) and Cluster Analysis (CA) were used to identify potential sources of pollution, while the Water Quality Index (WQI) provided an overall evaluation of water quality. The WQI score of 74.23 indicated generally good water quality, although localized contamination was observed. PCA results suggested that most heavy metals originated from anthropogenic activities, and CA grouped pollution sources into two main clusters. The geo-accumulation index showed low cadmium (Cd) levels at most stations, with slight to moderate pollution recorded at Station 5. Chromium (Cr), copper (Cu), and lead (Pb) exhibited moderate to strong pollution levels. Ecological risk assessment indicated no significant risk from Cr, low risk from Cu and Pb, and a very high ecological risk from Cd. The Heavy Metal Pollution Index (HPI), ranging from 290.35 to 294.75, further confirmed substantial human-related input. These findings highlight the need for routine monitoring and targeted remediation to prevent further degradation, safeguard aquatic ecosystems, and protect public health
Phylogenomic incongruence gives new perspectives on the taxonomic complexity of Muscari s.l. (Asparagaceae, Scilloideae)
Get PDFMuscari s.l. (Asparagaceae, Scilloideae) is a widespread genus of bulbous geophytes native to the Mediterranean, the Middle East and into the Caucasus. Based on inflorescence and floral morphology, four distinct groups have long been recognised and treated as either genera (Muscari s.str., Muscarimia, Leopoldia, Pseudomuscari) or subgenera within Muscari s.l. However, a recent molecular phylogenetic investigation proposed a new subgenus, Pulchella. Despite the several morphological and molecular phylogenetic investigations of Muscari, the delineation of taxa, either at the generic or subgeneric level, remains unstable. Here we aim to evaluate the monophyly and robustness of the recognised groups using broadly sampled nuclear (low‐copy number and ribosomal cistron) and plastome sequence phylogenies of Muscari s.l. Our morphological and molecular delineation of M. subg. Muscarimia and subg. Pseudomuscari across the analyses of three data sources are broadly congruent. However, high levels of incongruence within M. subg. Leopoldia and subg. Muscari are reported and discussed here, with implications for the stability of the newly described M. subg. Pulchella. Nomenclatural rules also require a new subgenus name to replace the name Pseudomuscari, which is shown to be a synonym of subgenus Muscari and has therefore been misapplied in recent work
Effect of the garlic matrix and inclusion level on in vitro methane production and fermentation
No full textGarlic contains bioactive organosulphur compounds reported to be effective in reducing methane (CH4) emissions, but garlic dietary supplements are inconsistent in reducing rumen CH4 production, possibly due to matrix or inclusion level effects. To assess this, the effects of garlic matrix (freeze-dried, FD; garlic extract, GE), source (Chinese; Spanish) and inclusion level (30, 60, 120 mg extract/g DM) on gas, CH4 and volatile fatty acid (VFA) production were measured using an in vitro gas production rumen fermentation system. Garlic extract was extracted from both sources, and this or FD garlic was incubated at the same oil inclusion levels in flasks with a dried, milled total mixed ration (TMR; forage:concentrate 50:50, DM basis) for 72 h, with strained rumen fluid and incubation medium (1:9, v/v). Flasks containing just TMR (control, CON) or no substrate (negative control) were also included. Gas pressure measured at intervals during the fermentation was converted to volume, and gas samples were analysed for CH4 concentration using gas chromatography. Dry matter degradability and VFA concentrations in the medium were measured after 72 h. In vitro gas and CH4 production was fitted to previously published models to obtain gas production kinetic characteristics. Data were analysed using linear mixed models, with processing method, origin, and their interaction as fixed, and run as random factors. Dry matter degradability (g/kg DM) was higher (P < 0.001) with all treatments (both FD and GE) for both Chinese and Spanish garlic across all inclusion rates (79.8 and 80.1) compared to CON (78.3). Total gas production (ml) was higher (P < 0.05) in the GE treatments than the CON (145.2) for both Chinese and Spanish garlic (164.1 and 169.1, respectively). Acetate:propionate ratio was lower (P < 0.001) for both garlic treatments and origin across all inclusion rates (2.4-2.9) compared with CON (3.0). Increasing the inclusion rate did not change in vitro CH4 production compared with CON. The results suggest that the bioactive components in garlic, when presented in an extracted matrix, might enhance overall fermentation efficiency without directly mitigating CH4 emissions. This finding implies that while garlic-based supplements might not consistently reduce CH4 emissions, they could be used to improve feed efficiency and animal productivity in ruminant systems
Challenging the overseer: enslaved women’s violent resistance in the US antebellum South
Get PDFThis article examines violent confrontations between enslaved women and white overseeing men, exploring how enslaved women opposed overseers through the weaponization of objects and fixtures on sites of enslavement across the antebellum South. Few studies have explored enslaved women’s weaponized resistance and how they shaped the landscape of the US slaveholding South for their own violent purposes. Guided by judicial records, fugitive narratives, and the testimony of the formerly enslaved, the cases included in this study illuminate how enslaved women radically re-interpreted violence for their own use, highlighting the complexity of their actions in slavery to include physical acts which occurred within and beyond the remit of self-protection. In creating a counter-conceptualization of armed violence, “Challenging the Overseer” considers the possibilities for, and uses of, enslaved women’s armed resistance against male overseers and underscores that female militance existed alongside the armed resistance of enslaved men, as more commonly portrayed in abolitionist materials. This examination aims to create a broader conceptualization of violence, one that diverges from the established focus on violence against women to open new discussions surrounding enslaved women’s own agentic use of physical force
Effects of American ginseng (Panax quinquefolius) extract on human neurocognitive function: a review
Get PDFCompared with Panax ginseng (Asian ginseng), Panax quinquefolius (American ginseng) has received relatively little research attention. Nevertheless, across several clinical trials a common finding is that P. quinquefolius extracts improve aspects of mood, mental fatigue, and cognitive function. This review details the findings from double-blind, randomized, controlled clinical trials which included assessment of cognitive performance, fatigue, or mood, individually or in combination. Limited fatigue
benefits were observed in cancer patients at high doses (2000mg). The most notable effects at lower doses (100mg-400 mg) included enhancement of attentional and working memory performance in healthy adults and in Schizophrenia patients. Several studies also highlighted potential mechanisms underlying the cognitive effects of P. quinquefolius. These include increased activation of frontoparietal neural circuits and, in the context of the gut-brain axis, alterations of the human gut microbiome composition. The effects are also consistent with cholinergic modulation. Such effects suggest that P. quinquefolius extract may have benefits to everyday cognitive function
Key action areas for population and planetary health: recommendations arising from the transforming the UK food systems programme
No full textThe UK food system faces critical challenges at the intersection of public health, environmental sustainability, and economic resilience. Currently contributing significantly to greenhouse gas emissions, biodiversity loss, and freshwater use, the system also fails to ensure universal access to healthy diets—particularly for lower-income populations during a cost-of-living crisis. The Transforming UK Food Systems (TUKFS) Programme has brought together academia, industry, policymakers, and communities to co-produce solutions to these complex challenges. This paper highlights findings from the Programme, with a focus on improving nutrition and sustainability. It outlines four key action areas: (1) innovation in manufacturing and supply chains, including development of UK-grown pulses, fortified foods, and aquaculture systems; (2) transforming food environments, such as school meals and supermarkets, to make healthy food more accessible; (3) empowering communities through co-production and stakeholder engagement across the food system; and (4) reforming policy and governance by aligning national and local strategies and applying systems thinking to food policy. Collectively, these actions aim to drive coordinated, evidence-based transformation toward a healthier, more equitable, and sustainable UK food system
Bioarcheological perspectives on the timing of adolescence in rural Avar‐age Austria, 7th–9th centuries CE
Get PDFObjectives: This study provides insights into adolescent development during the early medieval period in Austria and offers a point of comparison of the timing of sexual maturation relative to the Imperial Roman and the late medieval periods. Materials and Methods: The timing of adolescent development of 89 individuals in two rural cemeteries from the middle to late Avar period (ca. 650–800 CE) was reconstructed using skeletal and dental indicators. This is the first study to employ genetic sex estimation via ancient DNA on all analyzed adolescents, enabling robust assessment of sex‐specific patterns of growth and development. Results: Females were on average 1–2 years younger than males at each development stage. Adolescents appear to have developed later during the late Avar period compared to the previous Roman (0.4–2.3 years) and to a lesser extent later than the late medieval period (by up to 1.2 years). Discussion: These developmental differences may reflect the impact of different living conditions in urban and rural settings as well as underlying genetic variation. While general ages of adolescence were comparable between the early and later medieval groups, the earliest observed age of menarche is 3 years later in the later medieval period than in the Roman group. The timing of the physiological transition is consistent with an increase in grave goods in the early medieval sites. Greater standardization in puberty assessment, age, and biological sex estimation is needed to improve cross‐population comparability of future adolescence studies from different contexts in the past
Using landscape biodiversity metrics to assess rewilding: a comparison of the Knepp Estate and an agricultural baseline at Boothby Wildland
Get PDFThe biodiversity crisis is often framed in terms of the reduction of species found at a site: α (alpha) diversity. However, changes in species composition across a landscape—β (beta) diversity—caused by biotic homogenisation are part of the same crisis. Much biotic homogenisation in British terrestrial landscapes in the post‐war period (1945 onwards) has been driven by agricultural conversion and intensification. Restoration efforts must therefore contend with restoring agricultural land to some desired state, and rewilding has emerged as a potential solution to this problem. Here we quantify rewilding success by comparing α‐ and β‐diversity of plant assemblages across two study systems in different stages of rewilding. Boothby Wildland is an arable farm recently given over to rewilding, while the Knepp Estate is an ex‐arable and dairy farm currently >20 years into rewilding. We assessed α‐diversity within and β‐diversity across these two landscapes using 3 years of plant survey data (2022–2024). We confirmed expected differences between a baseline and rewilded landscape and explored the changes in a brand new rewilded landscape during its early years of progress. As expected, the plant community at the Knepp Estate is relatively stable while that of Boothby Wildland is changing rapidly and we discuss the landscape impacts of different herbivory regimes on recovery. Practical implication. We show that spatial metrics for phylogenetic diversity can distinguish between a rewilded and degraded landscape. This suggests that changes in the structure of biodiversity across landscapes can be quantified using analyses that account for spatial structure in metrics. We call for further research to test if a spatial approach of this kind can be used as a general metric of success in rewilding