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Agricultural practices that enhance soil structure improve crop yields of Swedish farms
Get PDFAgricultural intensification has increased crop yields but resulted in negative consequences for soil health. Here, we investigated the impact of agricultural practices on soil health and crop yields and their interactions across 67 farmer fields in Sweden. To investigate if those factors could explain differences in crop performance between fields, we asked each farmer to select a “good” field with high and/or stable yield and a contrasting “poor” field. At each field, we measured the soil health indicators: plant available water capacity, penetration resistance, wet aggregate stability, bulk density, cation exchange capacity, pH, soil organic matter content (SOM) and basal respiration. Five-year agricultural management information including tillage, crop rotation, application of organic fertilizers and pesticides, and crop yields were obtained from the farmers. Basal respiration was the most sensitive indicator, positively associated with higher crop diversity, more frequent organic fertilizer use, less frequent fungicide use, and lower tillage intensity. Benefits of less intense tillage on soil health was shown by positive relationships between tillage intensity to aggregate stability and SOM. Soil health indicators could not explain differences in yield between “good” and “poor” fields. However, in the “poor” fields, higher yield was associated with more frequent pesticide use, suggesting larger pest, disease and/or weed problems. In the “good” fields, higher crop yield was not directly related to specific practices but associated with higher aggregate stability and SOM and lower bulk density, highlighting the importance of prioritizing practices that enhance soil structure
Tailored droplet deposition strategies for direct printing of fully functional components via molten metal jetting
Get PDFMolten Metal Jetting (MMJ) is an emerging metal additive manufacturing technique with significant potential across various industries such as electronics, healthcare, aerospace, and robotics. In this process, components are built by depositing molten droplets one by one to form a 3D structure. Ensuring void-free deposition is essential for achieving high density, structural integrity, and electrical conductivity in printed parts. Despite its promise, current research lacks effective methods to fully eliminate internal voids which undermine the performance and functionality of the printed parts. This paper introduces a novel approach that applies tailored droplet deposition techniques to directly produce functional parts via MMJ, without the need for post-processing. Using tin as the printing material, this study evaluates density, electrical conductivity, and surface roughness in samples produced with four distinct methods at substrate temperatures of 150 °C, 100 °C, and 50 °C. The results show that each substrate temperature requires a specific approach, and the identified methods achieve fully dense, highly conductive, and smooth-surfaced parts. Furthermore, a method for printing on a low-temperature (50 °C) substrate was developed, effectively mitigating the influence of residual stress and enabling the fabrication of temperature-sensitive components. This research bridges a critical gap in MMJ by enabling the direct production of fully functional parts, paving the way for broader industrial applications of this technology
How do clinicians navigate end-of-life care with NIV/CPAP? A thematic analysis study
Get PDFOBJECTIVES: To explore barriers and facilitators to a good death in patients with respiratory disease when advanced respiratory support, including non-invasive ventilation (NIV) and continuous positive airway pressure (CPAP), is used. Specifically, we examined healthcare professionals' perspectives on what constitutes a good death in this context, how treatment failure is recognised, how decisions to continue or withdraw therapy are made, and the impact of providing this care on staff. DESIGN: Qualitative study using semistructured interviews and reflexive thematic analysis. SETTING: Secondary care services in a large UK National Health Service Trust, including acute medicine, general medicine, respiratory medicine and palliative care. PARTICIPANTS: 25 healthcare professionals (19 female, 6 male) from multidisciplinary backgrounds, including doctors, nurses and physiotherapists. Participants self-identified as experienced in the provision of NIV/CPAP at the end of life. Staff working primarily in intensive care units were excluded.None. OUTCOME MEASURES: Not applicable. RESULTS: Healthcare professionals described the complexity of caring for patients dying while receiving or recently withdrawn from NIV/CPAP. Five interrelated themes were identified: beliefs around dying well, symptom management during active treatment, recognition of treatment failure, negotiated decision-making and the process of withdrawal. Staff reported tensions between providing active treatment and ensuring comfort, inconsistent practices regarding symptom control and withdrawal, and conflicts within multidisciplinary teams. Nurses highlighted hidden psychological and relational labour in supporting patients, while doctors often described delays in decision-making to align families with treatment withdrawal. CONCLUSIONS: Caring for patients using NIV/CPAP at the end of life presents ethical, clinical and emotional challenges for staff, patients and families. Variation in practices and perspectives highlights the need for structured training, interdisciplinary approaches and greater recognition of the often hidden relational and emotional labour involved in this work, particularly among nursing colleagues. Further research should evaluate strategies to support consistent and compassionate withdrawal practices
Intra-cluster light as a dynamical clock for galaxy clusters: Insights from the MAGNETICUM, IllustrisTNG, Hydrangea, and Horizon-AGN simulations
Get PDFContext. As the most massive nodes of the cosmic web, galaxy clusters represent the best probes of structure formation. Over time, they grow by accreting and disrupting satellite galaxies, adding those stars to the brightest cluster galaxy (BCG) and the intra-cluster light (ICL). However, the formation pathways of galaxy clusters can vary significantly.Aims. To inform upcoming large surveys, we aim to identify observables that can distinguish galaxy cluster formation pathways.Methods. Using four different hydrodynamical simulations, Magneticum, TNG100 of IllustrisTNG, Horizon-AGN, and Hydrangea, we studied how the fraction of stellar mass in the BCG and ICL (fICL + BCG) relates to the galaxy cluster mass assembly history.Results. For all simulations, fICL + BCG is the best tracer for the time at which the cluster has accumulated 50% of its mass (zform), performing better than other typical dynamical tracers, such as the subhalo mass fraction, the halo mass, and the position offset of the cluster mass barycenter to the BCG. More relaxed clusters have a higher fICL + BCG, in rare cases up to 90% of all stellar mass, while dynamically active clusters have lower fractions, down to 20%, which we find to be independent of the exact implemented baryonic physics. We determine the average increase in fICL + BCG from stripping and mergers to be between 3–4% per gigayear. Furthermore, fICL + BCG is tightly traced by the stellar mass ratio between the BCG and both the second (M12) and fourth (M14) most massive cluster galaxy. The average galaxy cluster has assembled half of its halo mass by zform = 0.67 (about 6 gigayears ago), though individual histories vary significantly from zform = 0.06 to zform = 1.77 (0.8–10 giga years ago).Conclusions. As all four cosmological simulations consistently find that fICL + BCG is an excellent tracer of the cluster dynamical state, upcoming surveys can leverage measurements of fICL + BCG to statistically quantify the assembly of the most massive structures through cosmic time
Quantitative calibration of a traveling-wave parametric amplifier applied to an optomechanical platform
Get PDFIn the past decade, the microwave quantum electronics toolbox has been enriched with quantum limited detection devices such as traveling-wave parametric amplifiers (TWPAs). The extreme sensitivity that they provide is not only mandatory for some physics applications within quantum information processing, but is also the key element that will determine the detection limit of quantum sensing setups. In the framework of microwave optomechanical systems, an unprecedented range of small motions and forces is accessible, for which a specific quantitative calibration becomes necessary. We report on near quantum limited measurements performed with an aluminum drumhead mechanical device within the temperature range 4-400 mK. The whole setup is carefully calibrated, especially taking into account the power dependence of microwave absorption in the superconducting optomechanical cavity. This effect is commonly attributed to two-level systems (TLSs) present in the metal oxide. We demonstrate that a similar feature exists in the TWPA, and can be phenomenologically fitted with adapted expressions. If not taken into account, the error on the signal strength can be as large as a factor of about 2, which is unacceptable for quantitative experiments. The power and temperature dependence is studied over the full parameter range, leading to an absolute definition of the phonon population (i.e., Brownian-motion amplitude), with an uncertainty ±20% limited by sources of noise internal to the optomechanical element
Canine Ticks, Tick-Borne Pathogens and Associated Risk Factors in Nigeria
Get PDFTick-borne pathogens (TBPs) pose a significant threat to canine health in Nigeria. Despite this, there is little data on the molecular identification of ticks and TBPs of dogs in Nigeria. This study assessed the prevalence of ticks and TBPs in Nigerian dogs, along with associated risk factors. A total of 259 dogs were enrolled in the study, from which 112 adult ticks were collected. Of these, 40 were characterized by molecular barcoding confirming Rhipicephalus sanguineus (R. sanguineus, 35/40) and Haemphysalis leachi (H. leachi, 5/40) infestations. Nucleotide sequences showed high percentage similarity to R. sanguineus tropical lineage and H. leachi sequences from Chad. Point-of-care (POC) testing of 259 dogs detected antibodies to TBPs in 40.9% of blood samples, with Ehrlichia (29.7%), Anaplasma (10.8%), and Dirofilaria (0.4%) species identified. PCR assays revealed a prevalence of 58.7% for TBPs, including Ehrlichia (40.5%) and Babesia (17.4%), with 7.3% co-infected. Risk factor analysis showed that adult dogs and those infested with ticks had a higher likelihood of TBP seropositivity. Exotic breeds and dogs examined during the rainy season were more likely to test positive for TBPs via PCR. Overall, this study demonstrates the high prevalence of diverse TBPs in Nigerian dogs and suggests that dog breed may play a role in susceptibility to diseases
Modelling and Simulation of Surface Diffusion in Heterogeneous Porous Materials
Get PDFThe surface diffusion flux is known to dominate mass transport within many amorphous porous materials, used as adsorbents, heterogeneous catalysts, and membranes, employed in many chemical processes. However, while the impact of surface coverage has been widely studied and reviewed, relatively little attention has been paid to the impact of surface geometric and energetic heterogeneity on the surface diffusion rate, which would inform intelligent materials selection. It was, thence, the aim of this work to survey studies of the impact of surface structure on surface diffusion. Since the so-called “maximally realistic” modelling approach is found to be infeasible, due to limitations on the degree of structural characterisation possible for complex disordered surfaces, and the level of detail and length scales it is possible to represent with current computing power, a range of alternative approaches have been adopted. It has been seen that the Galilean idealisation of atomistic models has rendered them sufficiently tractable in order to study the impact of certain surface features, such as traps or ruts, on surface diffusion. Theoretical justifications have been used to develop minimalist models of amorphous surfaces, and mass transport thereon, that do selectively include the key surface parameters, and have, therefore, been successfully empirically validated for a range of different surfaces and adsorbate types
Clinical Role of the Noninvasive Abdominal Fetal ECG in the Detection and Monitoring of Fetal Tachycardia
Get PDFBACKGROUND: Fetal tachycardias can cause adverse fetal outcomes including ventricular dysfunction, hydrops, and fetal demise. Postnatally, ECG is the gold standard, but, in fetal practice, echocardiography is used most frequently to diagnose and monitor fetal arrhythmias. Noninvasive extraction of the fetal ECG (fECG) may provide additional information about the electrophysiological mechanism and monitoring of intermittent arrhythmias. Signal processing advances could provide improved data quality impacting clinical translation. The aim of this study was to assess the fetus with known or suspected tachycardia using noninvasive abdominal fECG and correlate results with fetal echocardiography and postnatal ECG. METHODS: Prospective recruitment of pregnant participants with known or suspected fetal tachycardia in a tertiary fetal cardiology unit. Overnight fECG recording at home using the MonicaAN24 monitor was performed. Data processing using bespoke MATLAB scripts was undertaken to produce fetal heart rate and beat-to-beat rhythm strips. Comparison of fECG data with clinical data obtained using echocardiography and postnatal findings. Data are presented as median (interquartile range; range). RESULTS: Fifteen participants undertook 1 to 4 fECG recordings, giving a total of 23 recordings. Gestational age was 28.9 (23.9-34.3; 21-39.1) weeks. Duration of recording was 512 (380-609; 5-1259) minutes. Intermittent tachycardia was demonstrated on fetal heart rate graphs. Rhythm strips correctly identified short-ventriculoatrial and long-ventriculoatrial tachycardia, atrial flutter, and sinus rhythm with findings correlating with echocardiography. Postnatal ECG correlation was possible in 3. CONCLUSIONS: We have shown that rhythm strips of fECG signals can be extracted and correctly identify the electrical mechanism of arrhythmia in cases of fetal tachycardia. The potential to monitor fetal heart rate over a prolonged period is an advantage over current monitoring strategies for documentation of intermittent arrhythmias and gauging the response to medical therapy. These data will enable research to focus on improvement in signal quality, assessment of other arrhythmia subtypes, and real-time ambulatory monitoring of the fetal rhythm
Efficacy and safety of sipavibart for prevention of COVID-19 in individuals who are immunocompromised (SUPERNOVA): a randomised, controlled, double-blind, phase 3 trial
No full textBackground: Sipavibart is an anti-spike monoclonal antibody that neutralises SARS-CoV-2 with exceptions, including Phe456Leu-containing variants (eg, KP.2* and KP.3*). This trial assessed sipavibart efficacy and safety for prevention of symptomatic COVID-19 in participants who are immunocompromised. Methods: In this ongoing, double-blind, international, phase 3 trial, we enrolled participants who were immunocompromised and aged 12 years or older at 197 hospitals, university health centres, and clinical trial units in 18 countries. Participants were randomly allocated 1:1 to a sipavibart group (intramuscular sipavibart 300 mg on days 1 and 181) or a comparator group (tixagevimab 300 mg–cilgavimab 300 mg on day 1 and placebo on day 181 or placebo on days 1 and 181), stratified by previous COVID-19 vaccination and infection status and use of tixagevimab–cilgavimab. The primary efficacy outcomes were symptomatic COVID-19 caused by any variant or symptomatic COVID-19 caused by non-Phe456Leu-containing variants within 181 days of dosing, assessed in the SARS-CoV-2-negative set, comprising all participants without a positive RT-PCR test for SARS-CoV-2 at baseline and who received at least one trial intervention dose. Safety outcomes for adverse events were assessed 90 days following the first dose and for serious adverse events throughout the study in the safety analysis set (ie, all participants who received at least one injection of sipavibart or comparator). This study is registered with ClinicalTrials.gov, NCT05648110. Findings: Participants were screened from March 31 to Oct 27, 2023; 3349 participants (56·8% female) were randomly assigned: 1674 to the sipavibart group (five no first dose; 1669 sipavibart) and 1675 to the comparator group (nine no first dose; 1105 tixagevimab–cilgavimab and 561 placebo). Within 181 days of dosing, 122 (7·4%) of 1649 participants in the sipavibart group and 178 (10·9%) of 1631 participants in the comparator group had symptomatic COVID-19 due to any variant (relative risk reduction [RRR] 34·9% [97·5% CI 15·0 to 50·1]; p=0·0006), 54 (3·3%) participants in the sipavibart group and 90 (5·5%) participants in the comparator group had symptomatic COVID-19 due to non-Phe456Leu-containing variants (RRR 42·9% [95% CI 19·9 to 59·3]; p=0·0012), and 47 (2·9%) participants in the sipavibart group and 64 (3·9%) participants in the comparator group had symptomatic COVID-19 due to Phe456Leu-containing variants (30·4% [–1·8 to 52·5]). Adverse events occurred in 833 (49·9%) of 1671 participants in the sipavibart group and 857 (51·5%) of 1663 participants in the comparator group within 3 months of the first dose. One COVID-19-related death occurred in the comparator group. Serious adverse events considered related to trial intervention occurred in two (0·1%) of 1671 participants in the sipavibart group and seven (0·4%) of 1663 participants in the comparator group (none fatal). No serious cardiovascular or thrombotic events were considered to be related to sipavibart. Interpretation: The primary analysis showed efficacy and safety of sipavibart in preventing symptomatic COVID-19 in participants who are immunocompromised when susceptible (ie, non-Phe456Leu-containing) variants dominated, although no efficacy was shown against resistant (ie, Phe456Leu-containing) variants that dominate as of November, 2024. Funding: AstraZeneca
A novel Toxoplasma gondii thioredoxin (TgTrx1) is important for parasite fitness and virulence
No full textThe protozoan parasite Toxoplasma gondii relies on antioxidant proteins and systems to protect against the host′s immune responses and to neutralize free radicals produced by its own metabolism. In this study, we identified and characterized a new thioredoxin protein, TgTrx1, which is mainly found in the cytoplasm of T. gondii tachyzoites and contains a conserved-CXXC-catalytic motif. Using CRISPR-Cas9 gene editing, we disrupted the TgTrx1 gene to generate a knockout strain (RHDtrx1) and studied the effect of gene loss on various aspects of the infection process. RHDtrx1 parasites showed a marked reduction in their ability to invade host cells, secrete microneme proteins, replicate intracellularly, egress from host cells, and tolerate oxidative stress. They also displayed abnormal mitochondrial morphology and asynchronous cell division. Transcriptomic analysis revealed significant changes in the expression of genes involved in oxidative stress response and bradyzoite differentiation. Mice injected intraperi-toneally with 10 6 RHDtrx1 tachyzoites showed no clinical symptoms. However, the immunity induced by these attenuated tachyzoites conferred only partial protection against subsequent acute and chronic T. gondii infections. This limited protective effect is likely related to the parasite′s impaired replication, which may lead to rapid clearance by the host immune system and insufficient antigenic stimulation to elicit a fully protective immune response. These findings establish TgTrx1 as a multifunctional redox protein important for T. gondii survival, redox balance, synchronous cell division, and virulence
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