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Cellular microbiology of gram-negative opportunistic pathogens of Achromobacter and Enterobacter species
No full textSpectral irradiance variability in Lyman-alpha emission during Solar flares
No full textThe Lyman-alpha (Lyα; 1216 Å) line is the brightest emission line in the quiescent solar spectrum and radiates a significant fraction of the available nonthermal energy during flares. Despite its importance, there is a lack of detailed studies of Lyα spectral variability during flares. Recently, spectrally resolved Lyα flare observations from the SORCE/SOLSTICE instrument have become available. This study examines Lyα spectral variability and its relationship with HXR emission from nonthermal electrons, using observations of two M-class flares from SORCE/SOLSTICE and RHESSI. Imaging observations from STEREO/SECCHI EUVI and SDO/AIA provide further context. Enhancements across the Lyα line profile were found to closely correlate with bursts of HXR emission, suggesting a primarily nonthermal origin. Red enhancement asymmetries at the peak of each flare were attributed to chromospheric evaporation, while blue wing enhancement and blue asymmetry were linked to a bright filament-eruption seen in SDO/AIA 1600 Å images. These findings contribute to the understanding of spectral Lyα variability during flares and highlight the need for future studies using a higher quality and quantity of spectral Lyα flare observations. Such studies will further characterise the physical mechanisms driving Lyα flare variability.<br/
Joint semantic transmission and resource allocation for intelligent computation task offloading in MEC systems
No full textMobile edge computing (MEC) enables the provision of high-reliability and low-latency applications by offering computation and storage resources in close proximity to end-users. Different from traditional computation task offloading in MEC systems, the large data volume and complex task computation of artificial intelligence involved intelligent computation task offloading have increased greatly. To address this challenge, we propose a MEC system for multiple base stations and multiple terminals, which exploits semantic transmission and early exit of inference. Based on this, we investigate a joint semantic transmission and resource allocation problem for maximizing system reward combined with analysis of semantic transmission and intelligent computation process. To solve the formulated problem, we decompose it into communication resource allocation subproblem, semantic transmission subproblem, and computation capacity allocation subproblem. Then, we use 3D matching and convex optimization method to solve subproblems based on the block coordinate descent (BCD) framework. The optimized feasible solutions are derived from an efficient BCD based joint semantic transmission and resource allocation algorithm in MEC systems. Our simulation demonstrates that: 1) The proposed algorithm significantly improves the delay performance for MEC systems compared with benchmarks; 2) The design of transmission mode and early exit of inference greatly increases system reward during offloading; and 3) Our proposed system achieves efficient utilization of resources from the perspective of system reward in the intelligent scenario.<br/
Self-informant convergence in dark tetrad traits: Examining relations with trait similarity, rateability, desirability and mental health
No full textHigher adherence to the EAT-Lancet reference diet is inversely associated with mortality in a UK population of cancer survivors
No full textBackgroundSignificant advancements in treatment and care, as well as early detection, have contributed to an increase in cancer survival rates. Recently, the EAT-Lancet Commission on Food, Planet, Health proposed the “planetary health diet” but to date, no study has investigated the potential associations between adherence to the EAT-Lancet reference diet and mortality in cancer survivors. To determine whether higher adherence to the EAT-Lancet reference diet is associated with lower risk for all-cause, cancer, and cardiovascular mortality in cancer survivors.MethodsData from the prospective UK Biobank study were used. Information from UK Biobank’s Touchscreen questionnaire was used to develop a score reflecting adherence to the EAT-Lancet reference diet. Cox proportional hazards regression was used to assess the association of the EAT-Lancet reference diet score with all-cause, cancer, and cardiovascular mortality in cancer survivors.ResultsWithin 25,348 cancer survivors, better adherence to the EAT-Lancet reference diet was inversely related to all-cause mortality (hazard ratio (HR): 0.97, 95% confidence interval (CI): 0.95–0.99), 1 unit increase) and cancer mortality (HR: 0.98, 95% CI: 0.96–1.00), while mostly null associations were observed for major cardiovascular mortality (HR: 0.99, 95% CI: 0.95–1.03).ConclusionsOur findings suggest the adoption of the EAT-Lancet reference diet is associated with lower all-cause and cancer-specific mortality among cancer survivors
Effect of age and sex on the urinary elimination of a single dose of mixed flavonoids: results from a single-arm intervention in healthy UK adults
No full textBackgroundNutrition intervention trials demonstrate that increased flavonoid intake can have clinically meaningful impacts on disease outcomes/biomarkers; however, high variability in absorption and metabolism and large heterogeneity in biochemical and physiological responses are observed. The etiology of this variability is poorly understood.ObjectiveTo explore the relationships between sex, age, and microbiota speciation on mixed flavonoid elimination over 24 hour (h).MethodsHealthy males and females (n=163) prospectively recruited on the basis of age (18-30y or 65-77 y) and sex, consumed a standardized flavonoid-rich test meal providing 640mg of cocoa/chocolate flavan-3-ols, 340mg of citrus flavanones, and 390mg of blackberry anthocyanins. Urinary samples collected at baseline (-24 h to 0 h), 0-3.5 h, >3.5h-7 h and >7-24 h were analysed for flavonoids and their metabolites by Ultra high-performance liquid chromatography-mass spectrometry (UPLC-MS/MS). Stool microbiome speciation was determined via Illumina sequencing. Linear mixed-effect models were used to assess differences in cumulative excretion across age and sex with time-by-group interaction taken as the principal analysis of effect.ResultsThere were no group (older females, older males, younger females, younger males) differences in total 24 h urinary metabolite recovery, but there was a trend towards a higher rate of cumulative recovery in older males at 24h (β (95% CI) -61.4 (-107, -16.0 younger males compare to older males; P-group at 24hr=0.06). Of 76 metabolites, 20 had significantly different Tmax by age and 9 by sex, with a later mean Tmax observed for older participants (92% of instances). Associations with age were not mediated by BMI or microbiome speciation. Significant differences in Cmax by sex were observed for only 6 metabolites and differences by age for 5 metabolites.ConclusionTotal elimination recovery of (poly)phenols was relatively consistent across age and sex groups, while elimination kinetics differed substantially; possibly resulting from differences in intestinal transit time or kidney clearance. Assuming (poly)phenol metabolites have varying biological activities, establishing dose response relationships, and defining metabolite profiles in population subgroups is required to inform the future development of dietary flavonoid/(poly)phenol recommendations
New tetrabutylphosphonium organic ionic plastic crystals incorporating borate anions
No full textOrganic plastic crystals have seen rapid growth in their development and potential application as solid-state electrolytes in electrochemical devices. Two tetrabutylphosphonium ([P4444]+) salts incorporating non-halogenated bis(butane-1,4-dioxy)borate ([B(bdo)2]−) and tetrakis(pyrazolyl)borate ([B(pyr)4]−) anions have been synthesised and their physicochemical properties characterised. Both [P4444][B(pyr)4] and [P4444][B(bdo)2] are solid under ambient conditions and display solid–solid thermal phase transitions suggesting the formation of plastic crystal phases, which was confirmed by observation of significant ionic conductivity and ion mobility in the solid state. [P4444][B(pyr)4] showed more extensive polymorphism and greater ionic conductivity, and from the 31P linewidth NMR the phosphonium cation exhibited diffusion at lower temperatures. Therefore, these are of interest as potential new halogen-free solid-state electrolyte materials.<br/
Dual role of human activities and climate in pre-industrial nitrogen shifts in Ireland
No full textPast research has uncovered a shift in herbivore collagen δ15N values during the Middle to Late Bronze Age (3700–2750 BP) in Ireland, attributed to intensified land-use - another example in a growing body of evidence that suggests that the Anthropocene concept (whereby humans have made significant impacts to the Earth's systems) began far earlier than previously thought (the ‘Palaeoanthropocene’). While human activity was clearly an important driver of this shift, it remains possible that climate may also have played a role. In Ireland, this shift in δ15N appeared to be sustained despite subsequent reforestation, suggesting that Bronze Age and later peoples left a profound biogeochemical mark on the environment. Here, we revisit this topic, presenting new stable isotope (δ15N and δ13C) measurements from directly radiocarbon-dated wild and domesticated adult herbivorous ungulate bones from the Bronze and Iron Ages, with the aim of constraining the timing of this shift and disentangling the role of human land use from climatic influences. A sustained nitrogen isotopic shift was constrained to ca. 3000 cal BP. Notably, during the Iron Age, a time of widespread reforestation, wild and domesticated herbivorous ungulates exhibited δ15N values that were not significantly different from one another. This suggests that, while the δ15N shift was initiated by land-use change, climate variability, particularly shifts towards warmer and drier conditions during the Late Bronze/Iron Age transition and later Iron Age, may have contributed to its persistence. This study refines the chronology of nitrogen cycle changes in Ireland, demonstrating that human activity initiated a long-term shift in δ15N values during the Late Bronze Age, but that climatic factors may have played a role in maintaining elevated δ15N values during periods of reduced land use. These findings underscore the complexities of understanding the nitrogen cycle in ancient environments and highlight the potential interplay between anthropogenic and environmental drivers of biogeochemical change.<br/
Dynamic changes of aqueous matrix metalloproteinases and imaging correlation in retinal vein occlusion following ranibizumab therapy
No full textPurpose: To investigate changes in aqueous humor matrix metalloproteinases (MMPs) after intravitreal ranibizumab (IVR) therapy, and their correlations with imaging parameters in retinal vein occlusion (RVO).Methods: Aqueous humor samples from 28 patients with RVO were collected at baseline, 1, and 2 months after IVR therapy. MMP-1, -2, -3, -7, -8, -9, -10, TIMP-1, and VEGF-A levels were measured using Luminex × MAP. Participants were categorized as responders or nonresponders based on ≥ 30% central retinal thickness (CRT) reduction at month 2. MMPs and TIMP-1 changes were analyzed. Correlations between baseline MMP-1, MMP-2, TIMP-1, and retinal structural and microvascular parameters were assessed. Multivariate regression analyzed associations with treatment response.Results: Intraocular MMP-1, MMP-2, and TIMP-1 levels significantly decreased in responders but not in nonresponders. Baseline MMP-1, MMP-2, and TIMP-1 were positively correlated with CRT, IS–OS and ELM disruption, DRIL, and SRD height (all P < 0.05). Negative correlations were observed between MMP-1 (r = −0.520, P = 006), TIMP-1 (r = −0.416, P = 0.039), and FAZ size. Higher baseline MMP-1 (P = 0.024) and lower TIMP-1 (P = 0.034) levels were associated with greater CRT reduction.Conclusion: Aqueous humor levels of MMP-1, MMP-2, and TIMP-1 are associated with in macular edema, retinal damage, and microvascular changes in RVO. Baseline MMP-1 and TIMP-1 may serve as potential biomarkers for predicting short-term therapeutic response