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The relationship between warm and hot gas-phase metallicity in massive elliptical galaxies and the influence of active galactic nucleus feedback
No full textContext. Warm ionized gas is ubiquitous at the centers of X-ray bright elliptical galaxies. While it is believed to play a key role in the feeding and feedback processes of supermassive black holes, its origins remain under debate. Existing studies have primarily focused on the morphology and kinematics of warm ionized gas.Aims. This work aims to provide a new perspective on warm (∼10 000 K) ionized gas and its connection to X-ray-emitting hot gas (> 106 K) by measuring and comparing their metallicities.Methods. We conducted a joint analysis of 13 massive elliptical galaxies using MUSE/VLT and Chandra observations. Emission-line ratios, including [OIII]/Hβ, [NII]/Hα, were measured using MUSE observations to infer the ionization mechanisms. We derive metallicities of the warm ionized gas using HII, and LINER calibrations. We also computed the warm phase metallicity using X-ray/EUV, and pAGB star models. For two sources at higher redshifts, the direct Te method was also used to measure warm gas metallicities. The metallicity of the hot gas was measured using Chandra X-ray observations.Results. Our observations reveal that most sources exhibit composite ionization, with contributions from both star formation and LINER-like emission. The four sources with the lowest star formation rates in our sample – Centaurus, M87, M84, and Abell 496 – are dominated by LINER emission. A positive linear correlation was found between the gas-phase metallicities of the warm and hot phases, ranging from 0.3 to 1.5 Z⊙. In some sources the warm gas metallicity shows a central drop. A similar radial trend has been reported for the hot gas metallicity in some galaxy clusters.Conclusions. The ionization mechanisms of cooling flow elliptical galaxies are diverse, suggesting multiple channels for powering the warm ionized gas. The positive correlation found in warm and hot gas metallicities suggest the intimate connection between the two gas phases, likely driven by gas cooling and/or mixing. The large variation in the warm gas metallicity further suggests that cold gas mass derived under the assumption of solar metallicity for the CO-to-H2 conversion factor needs to be revised by approximately an order of magnitude
Effects of land use type on soil aggregate stability and organic carbon fractions in the He Huang Valley, Qinghai-Tibet plateau
Get PDFSoil aggregation plays a vital role in stabilizing soil organic carbon (SOC), with SOC dynamics within aggregates closely linked to sequestration. These processes are shaped by land use through variations in inputs, microbial activity, and decomposition. We assessed SOC, particulate organic carbon (POC), and mineral-associated organic carbon (MAOC) across aggregate-size classes under five land-use types in the He Huang Valley, Tibetan Plateau: natural grassland (NGL), terrace land (TL), facility land (FL), irrigated farmland (IFL), and abandoned land (AL). SOC content varied significantly by land use and depth, with the highest levels observed in NGL and FL (16.33 g kg−1 and 15.50 g kg−1, respectively) at surface depths, and marked depletion under TL and AL. MAOC dominated SOC across most aggregates, particularly in finer fractions, while POC was mainly concentrated in large macroaggregates under NGL (10.83 g kg−1). POC decreased with depth, whereas MAOC remained relatively stable. Greater MAOC accumulation in FL and IFL microaggregates suggests enhanced mineral stabilization under intensive use. Conversely, TL showed the lowest POC/MAOC ratios, reflecting reduced sequestration potential. Aggregate-associated SOC was strongly correlated with aggregate stability parameters and soil nutrients. Our findings highlight that land use significantly alters aggregate structure and SOC fractionation, with NGL and FL showing the highest potential for carbon stabilization in semi-arid ecosystems
Outcomes following nurse-led day-case paracentesis
No full textBackgroundTherapeutic paracentesis (TP) is a key symptom-relieving intervention in refractory ascites. In response to rising demand, Nottingham University Hospitals NHS Trust was among the first UK centres to introduce a nurse-led, day-case TP service. This study evaluates the complications and mortality associated with this service.MethodsRetrospective analysis was undertaken on patients with decompensated cirrhosis who underwent nurse-led day-case TP between 1 January 2017 and 31 December 2021. Clinical and outcome data were systematically collected.ResultsA total of 2,530 TP procedures were performed on 340 patients. Minor (self-limiting) complications occurred in 54 cases (2.1%). In 22 cases (0.9%), patients were admitted to hospital within 7 days of TP – the reasons for admission were bacterial peritonitis (n = 11), abdominal pain (n = 3), and leakage of ascitic fluid (n = 7) or bleeding (n = 1) from the puncture site. There were no cases of abdominal visceral perforation or in-hospital deaths among those admitted.About 290 patients were included in 1-year survival analysis. About 177 (61%) were alive 1 year after their first TP. The median time from first TP to death was 125 days (IQR 43–210). The 30- and 90-day mortality rates after TP were 21.0% and 33.1%, respectively. Older age (p < 0.001), hepatocellular carcinoma (p < 0.001) and ongoing alcohol use (p < 0.001) were independently associated with 1-year mortality.ConclusionNurse-led, day-case TP is an effective and safe approach for managing refractory ascites in decompensated cirrhosis. Mortality remains high, particularly in patients with hepatocellular carcinoma and ongoing alcohol use
Transient bimodal effects in the in-line particle size measurement during milling of solid state materials
Get PDFFor the processing or synthesis of solid state materials, ball milling has proven to be an effective method. However, due to the continuous agitation, the process is not suited for in-situ measurement techniques. In this work, a system for the in-line particle size measurement during milling has been developed and tested. The results show that milling of a sample with a certain mean particle size results in the production of a bimodal size distribution before a final product with the smaller particle size is produced. Moreover, a much faster than expected reduction in size was achieved, whose time evolution could otherwise only be followed by wasteful and time-consuming specimen analysis in intervals. In conclusion, in-line particle size measurement during milling is a promising technique to optimize the processing time or obtain a product powder in a certain condition
Cobalt hydroxide to ZIF-67: A novel water-based electrochemical deposition
Get PDFThis study presents, a novel approach to electrochemically deposit continuous ZIF-67 films with controlled thickness. ZIF-67 is a zeolite imidazolate framework material comprised of tetrahedral cobalt (Co) cations and 2-methylimidazolate (HMim) linker in a zeolite-like sodalite (SOD) topology. We firstly deposited a layer of cobalt hydroxide (Co(OH)2) then the hydroxide layer was cathodically transformed to highly crystalline ZIF-67 films in HMim solution. Parameters such as concentrations of reactants, number of cyclic voltammetry (CV) scans and electrodeposition time were investigated while water was used as the solvent.Results showed that low concentrations of metal salt (Co(NO3)2 < 0.05 M) and linker (HMim < 1.75 M) were not sufficient to form a continuous coverage of either (Co(OH)2) or ZIF-67, respectively. Using a concentration of 0.099 M Co(NO3)2 and 1.75 M HMim yielded in ZIF-67 films with high crystallinity and homogeneous morphology. Increasing the electrodeposition time from 5 to 60 min showed a remarkable change in the ZIF-67 surface coverage (from 67% to 100%, respectively based on the morphological coverage). Film thickness was increased from 0.83 ± 0.12 μm to 3.00 ± 0.18 μm by increasing the number of CV cycles from 2 to 15, respectively. The developed approach was tested for scaling up the three-electrode cell from coating a 1 X 4 cm2 substrate to 25 X 25 cm2 in which the deposited scaled up ZIF-67 films had the same morphology and crystallinity of the small-scale substrate.Finally, the feasibility of using the developed films in the application of electrooxidation of methanol was explored. The developed films demonstrated a potential and consistent cycling performance across 50 cycles
A Cross-Sectional Content Analysis Exploring Women’s Experiences of Family Support Towards Tandem Breastfeeding in a Global Facebook Group sample
Get PDFObjectives: This study explored how tandem-feeding mothers felt supported or unsupported by their family members, to identify common responses to this breastfeeding practice. Methods: Free-text data were collected via an online questionnaire from a global sample of 1,209 tandem-feeding mothers. An emergent content analysis was conducted on 795 statements describing supportive experiences and 1,342 statements describing unsupportive experiences. Coding categories were developed inductively from the data. Results: Five coding categories emerged from supportive comments and seven from unsupportive comments. The most prevalent supportive categories were normalisation of breastfeeding and respect for the mother’s choice (52%), emotional support and encouragement (19%), and support provided without specific context (11%). The most prevalent unsupportive categories were questioning, challenging or pressuring mothers to stop tandem feeding (34%); disapproving comments, gestures or insults that caused mothers to feel uncomfortable (22%); and misinformed comments about tandem feeding (18%). Conclusions for Practice: Tandem-feeding mothers frequently experience both support and opposition from family members, with unsupportive responses often characterised by judgment and misinformation. These findings highlight the need for increased education and visibility of tandem feeding to normalise this practice and reduce stigma. Improving family understanding of tandem feeding may enhance social support for mothers and contribute to more positive breastfeeding experiences
Knowledge Related to Blood Donation and Iron, and Willingness to Take Iron Supplements Among Blood Donors in Multiple Countries
Get PDFFrequent blood donation can deplete iron stores, increasing the risk of iron deficiency anemia. Postdonation iron supplements may help preserve donor health, but willingness to take supplements likely depends on donor knowledge and confidence. We conducted a cross-sectional survey among 5691 whole blood donors from 6 countries (Netherlands, USA, Japan, Finland, Sweden, Germany). Knowledge was assessed using 16 true-or-false statements on 4 blood donation-related topics; confidence by asking if donors were "certain" or "guessing." Willingness to take supplements was assessed using 3 scenarios: to continue donating, when advised by a donor physician, and general iron supplementation rejection. Using logistic regressions, we assessed associations between knowledge, confidence, and willingness to take iron supplements for each scenario, adjusted for sex, age, country, prior supplement use, and trust in the blood service. Most donors exhibited medium to high knowledge and under confidence in that knowledge. Willingness to take supplements was high (80.6%-84.2% across scenarios). Knowledge and confidence were not consistently associated with willingness to take supplements. In contrast, trust in the blood service (odds ratio [OR] = 1.64, P < .001) and prior supplement use (OR = 1.87, P < .001) were strongly associated with willingness when supplements were required to continue donating, with similar effects across other scenarios. Willingness varied across countries, with higher willingness in Nordic countries. These findings suggest that trust-building approaches may be more promising than education-focused strategies, though causal relationships require further research. High acceptance rates suggest that postdonation iron supplementation may be a feasible strategy for donor iron management
Could living space provision in the first lactation have long term effects on milk production in housed dairy cows?
Get PDFThe productive life of a dairy cow centres milk production, reproduction, and health status. Current management practices, including living space provision, for first lactation animals are highly variable and associated with large impacts on reproduction and milk production. The aim of this investigation was to explore the potential lifetime effects on milk production when primiparous cows are provided with additional living space. This prospective study used two cohorts of cows from a previous randomised controlled trial that used matched pairs of cows, with one in each pair provided with 3m2 living space (“Control”) and the other 6.5m2 living space (“High”). In terms of lifetime milk production, the high space group consistently performed better; mean milk volume per lifetime day in the control space group was 37.55L versus 38.92L in the high space group. A random effects model was used to account for repeated measures within cow and revealed significant and substantially increased milk production in the high space group at less than 400 days in milk, between 800–1000 days in milk and greater than 1200 days in milk, compared the control space cohort. A Cox-Proportional hazards model was built to investigate time to herd exit, no difference was identified between the groups. This research allows cautious insights into the potential for the impact of increased space allowance for primiparous dairy cows on lifetime milk production. This could have important implications relating to societal perception, health, welfare, economics and environment impact, which could aid more sustainable approaches to managing dairy cows
Within-field variation in root-to-shoot ratios and root traits in spring barley: Implications for estimating carbon inputs
Get PDFRoots are a major pathway for carbon (C) input into agricultural soils, yet field-scale measurements of belowground C inputs and associated root traits remain limited. Consequently, many soil carbon models rely on fixed root-to-shoot ratios, and root trait variability is rarely considered. In this study, we quantified within-field variation in root-to-shoot ratios and root traits (root diameter, root length density and root tissue density) in spring barley (Hordeum vulgare L.) grown in southwestern Sweden in soil classified as Stagnic Eutric Cambisol, Eutric Stagnosol or Haplic Phaeozem according to the World Reference Base system. Roots (0–40 cm) and shoots were sampled during early to mid-reproductive stage, i.e. milking/early dough development stage, in a 50 × 50 cm grid at 11 sampling locations in the same field in two consecutive years. Shoot and root biomass were not correlated, resulting in variable root-to-shoot ratios (quartile coefficients of variation 7–18 %) and no consistent spatial pattern between years. Root traits displayed clear between year and depth variation, with coarser roots in the topsoil and root tissue densities and root length densities shifting across the profile, reflecting the highly plastic nature of root systems. The spatial variation in root properties in the field could not be explained by basic soil properties. Our findings call for a more mechanistic understanding of the drivers for root-to-shoot ratios and the plastic response of root traits to improve field-scale estimates of root-derived C inputs and SOC modelling accuracy
Development of a qPCR assay for Fasciola spp. identification and a deep amplicon sequencing method for differentiation of fluke species in UK livestock
Get PDFBACKGROUND: Trematode parasites, or flukes, are a significant economic threat to ruminant production worldwide. Traditional diagnostic methods rely on egg sedimentation from faeces, a time-consuming methodology lacking sensitivity and specificity. This study aimed to develop and validate two detection methods: firstly, qPCR for accurate identification of Fasciola spp., and secondly, a deep amplicon sequencing technique for identifying fluke species using faecal sedimented egg DNA. METHODOLOGY: To detect Fasciola spp., infection, primers targeting mitochondrial DNA were repurposed to develop a SYBR Green qPCR assay. For the identification of fluke species, a deep amplicon sequencing approach was developed. A reference sequence library and taxonomy file were generated for 21 fluke species, potentially enabling species-level sequence read separation for a range of trematodes and extraction of amplicon sequence variants (ASVs). To validate the qPCR and deep amplicon sequencing approach, 402 faecal samples were collected from cattle and sheep across the UK. Fluke eggs were isolated by sedimentation, screened by microscopy and qPCR, Sanger sequencing and deep amplicon sequencing to identify fluke eggs to species level. RESULTS: qPCR demonstrated high analytical sensitivity, detecting Fasciola hepatica DNA down to 19.2 fg and F. gigantica down to 6.4 fg, with no cross-amplification of other flukes. Deep amplicon sequencing was able to detect as few as five F. hepatica and Calicophoron daubneyi eggs and identify mixed infections. High levels of co-infection (14.4%) of F. hepatica and C. daubneyi were observed in faecal samples, followed by single infections with C. daubneyi (12.6%) and F. hepatica (3.2%). Notably, deep amplicon sequencing detected F. hepatica in 20 samples missed by qPCR. Data analysis identified 55 and 32 ASVs for F. hepatica and C. daubneyi, respectively, with phylogenetic clustering within their respective clades. CONCLUSION: This study developed a qPCR assay for Fasciola spp. detection and validated a deep amplicon sequencing for fluke species differentiation. These approaches are able to identify fluke species in excreta from infected ruminants and provide additional valuable tools for enhancing fasciolosis surveillance and control
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