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Search for a light charged Higgs boson in t -> H(+/-)b decays, with H(+/-) -> cs, in pp collisions at root s = 13 TeV with the ATLAS detector
No full textA search for a light charged Higgs boson produced in decays of the top quark, t → H±b with H± → cs, is presented. This search targets the production of top-quark pairs t ¯t → WbH±b, with W → ℓν (ℓ = e,μ), resulting in a lepton-plus-jets final state characterised by an isolated electron or muon and at least four jets. The search exploits b-quark and c-quark identification techniques as well as multivariate methods to suppress the dominant t ¯t background. The data analysed correspond to 140 fb−1 of pp collisions at √ s = 13 TeV recorded with the ATLAS detector at the LHC between 2015 and 2018. Observed (expected) 95% confidence-level upper limits on the branching fraction B(t → H±b), assuming B(t → Wb) + B(t → H± (→ cs)b) = 1.0, are set between 0.066% (0.077%) and 3.6% (2.3%) for a charged Higgs boson with a mass between 60 and 168 GeV.ATLAS Collaboratio
Swift-BAT GUANO Follow-up of Gravitational-wave Triggers in the Third LIGO-Virgo-KAGRA Observing Run
No full textWe present results from a search for X-ray/gamma-ray counterparts of gravitational-wave (GW) candidates from the third observing run (O3) of the LIGO–Virgo–KAGRA network using the Swift Burst Alert Telescope (Swift- BAT). The search includes 636 GW candidates received with low latency, 86 of which have been confirmed by the offline analysis and included in the third cumulative Gravitational-Wave Transient Catalogs (GWTC-3). Targeted searches were carried out on the entire GW sample using the maximum-likelihood Non-imaging Transient Reconstruction and Temporal Search pipeline on the BAT data made available via the GUANO infrastructure. We do not detect any significant electromagnetic emission that is temporally and spatially coincident with any of the GW candidates. We report flux upper limits in the 15–350 keV band as a function of sky position for all the catalog candidates. For GW candidates where the Swift-BAT false alarm rate is less than 10⁻³ Hz, we compute the GW– BAT joint false alarm rate. Finally, the derived Swift-BAT upper limits are used to infer constraints on the putative electromagnetic emission associated with binary black hole mergers.Gayathri Raman, Samuele Ronchini, James Delaunay, Aaron Tohuvavohu, Jamie A. Kennea, Tyler Parsotan, and Elena Ambrosi, Maria Grazia Bernardini, Sergio Campana, Giancarlo Cusumano, Antonino D, Aì, Paolo D, Avanzo, Valerio D, Elia, Massimiliano De Pasquale, Simone Dichiara, Phil Evans, Dieter Hartmann, Paul Kuin, Andrea Melandri, Paul O, Brien, Julian P. Osborne, Kim Page, David M. Palmer, Boris Sbarufatti, Gianpiero Tagliaferri, Eleonora Troja, The LIGO Scientific Collaboration, The Virgo Collaboration, and The KAGRA Collaboration (A. G. Abac ... et al.
Lower birth rate, greater female dementia risk: global and regional patterns and public health implications
No full textAims: This study investigates the relationship between national birth rate and female dementia incidence globally, considering demographic and socioeconomic confounders. Materials & methods: Data from 204 countries were analyzed using bivariate correlation, partial correlation, principal component analysis, and multiple linear regression. Female dementia incidence rate (FDIR) was the dependent variable. Birth rate served as the main predictor, with ageing (life expectancy), genetic predisposition (Biological State Index), economic affluence (GDP PPP), and urban living as confounders. Results: Birth rate demonstrated a significant inverse correlation with female dementia incidence (Pearson’s r = −0.772, p < 0.001), remaining robust after adjusting for confounders (partial r = −0.548, p < 0.001). Stepwise regression confirmed birth rate as the strongest independent predictor, explaining 61.6% of the variance in FDIR. Genetic predisposition and ageing were also significant, while economic affluence and urban living had minimal effects. The inverse relationship was more pronounced in developing countries and low-income regions. Conclusions: Lower birth rates were strongly associated with higher female dementia incidence globally. Birth rate should be considered a critical demographic factor in dementia risk prediction and public health planning, particularly in ageing and low-resource settings.Wenpeng Yo
ROBIN: Reference observatory of basins for international hydrological climate change detection.
No full textHuman-induced warming is modifying the water cycle. Adaptation to posed threats requires an understanding of hydrological responses to climate variability. Whilst these can be computationally modelled, observed streamflow data is essential for constraining models, and understanding and quantifying emerging trends in the water cycle. To date, the identification of such trends at the global scale has been hindered by data limitations – in particular, the prevalence of direct human influences on streamflow which can obscure climate-driven variability. By removing these influences, trends in streamflow data can be more confidently attributed to climate variability. Here we describe the Reference Observatory of Basins for INternational hydrological climate change detection (ROBIN) – the first iteration of a global network of streamflow data from national reference hydrological networks (RHNs) – comprised of catchments which are near-natural or have limited human influences. This collaboration has established a freely available global RHN dataset of over 3,000 catchments and code libraries, which can be used to underpin new science endeavours and advance change detection studies to support international climate policy and adaptation
Microplastics in soils: A comparative review on extraction, identification and quantification methods
No full textMicroplastics (MPs) have been continuously accumulating in soil, posing significant environmental concerns due to their potential toxicity and role as pollutant vectors. Effective monitoring of MPs in soils requires appropriate methods for extraction, identification and quantification. This comparative review systematically examined various methods used in MP analysis from solid matrix environments, highlighting the advantages and disadvantages of each technique. Soils are heterogeneous and complex matrices, which can interact differently with MPs, rendering the separation of MPs from soils a significant challenge. Key challenges include the interactions between MPs and soil organic matter and detection limitations of smaller size MP which can interfere with accurate extraction. Specialized techniques and devices are required for precise identification and quantification. Digestion can be effective in removing organic matter, although harsh digestion can degrade MPs. To improve the liability of MP analysis, it is critical to minimize steps that may reduce accuracy such as filtration, harsh digestion and inappropriate sample size. Conversely, adjusting or combining methods can enhance the precision of MP analysis. This review offers a forward-looking perspective by advocating extraction and detection approaches, thus providing a more accurate, reproducible and holistic framework for MP analysis in soils. These insights are anticipated to guide future research promote standardized protocols and enhance environmental monitoring efforts.Yoonjung Seo, Venkata Chevali, Yunru Lai, Zhezhe Zhou, Guangnan Chen, Paulomi Burey, Shaobin Wang, Pingan Son
Multi-Omics and Physiological Analysis Reveal Crosstalk Between Aphid Resistance and Nitrogen Fertilization in Wheat
No full textThe availability of nitrogen (N) can dramatically influence crops resistance to herbivorous insects. However, the interaction between N fertilization and crop resistance to insects is not well understood. In this study, the effects of N fertilization on the grain aphid (Sitobion miscanthi) were investigated using three wheat (Triticum aestivum) cultivars with different aphid resistances. We measured aphid life cycle parameters, fecundity, survival rate, weight and feeding behavior, in conjunction with wheat metabolomics, transcriptomics and alien introgression analysis. Our results demonstrated that higher N application benefits aphid feeding across all three wheat cultivars. We also reveal that the highly resistant cultivar (ZM9) can only exert its resistance‐advantage under low N fertilization, losing its advantage compared to moderately resistant cultivar YN19 and susceptible cultivar YN23 under higher N fertilization. The effects of N fertilization on wheat‐aphid interactions were due to changes in the regulation of carbon and nitrogen metabolism. Integration of multi‐omics highlighted specific aphid‐induced differentially expressed genes (DEGs, e.g., TUB6, Tubulin 6; ENODL20, Early nodulin‐like protein 20; ACT7 Actin 7; Prx47, Peroxidase 47) and significantly different metabolites (SDMs, e.g., crotonoside, guanine, 2′‐O‐methyladenosine, ferulic acid) in ZM9. Additionally, we report the unique SDMs‐DEGs interactions, associated with introgression during wheat domestication, may help infer aphid resistance. In summary, this study provides new insights into the relationships between N fertilization practices, defense responses and integrated pest management for sustainable wheat production.Yuanyuan Wang, Bin Di, Ze Sun, Sonali, Michelle Donovan-Mak, Zhong-Hua Chen, Man-Qun Wan
Search for a diffuse flux of photons with energies above tens of PeV at the Pierre Auger Observatory
No full textDiffuse photons of energy above 0.1PeV, produced through the interactions between cosmic rays and either interstellar matter or background radiation fields, are powerful tracers of the distribution of cosmic rays in the Galaxy. Furthermore, the measurement of a diffuse photon flux would be an important probe to test models of super-heavy dark matter decaying into gamma-rays. In this work, we search for a diffuse photon flux in the energy range between 50PeV and 200PeV using data from the Pierre Auger Observatory. For the first time, we combine the air-shower measurements from a 2km² surface array consisting of 19 water-Cherenkov surface detectors, spaced at 433 m, with the muon measurements from an array of buried scintillators placed in the same area. Using 15 months of data, collected while the array was still under construction, we derive upper limits to the integral photon flux ranging from 13.3 to 13.8km⁻² sr⁻¹ yr⁻¹ above tens of PeV. We extend the Pierre Auger Observatory photon search program towards lower energies, covering more than three decades of cosmic-ray energy. This work lays the foundation for future diffuse photon searches: with the data from the next 10 years of operation of the Observatory, this limit is expected to improve by a factor of ∼ 20.Pierre Auger Collaboratio
Smart Fluorosurfactant-Assisted Microfluidics Powered On-Demand Generation and Retrieval of Cell-Laden Microgels
No full textMicrofluidics have been widely employed as powerful tools to fabricate monodisperse, cell-laden hydrogel microdroplets with precise control for various biological applications, particularly in tissue engineering. While these systems enable high-throughput production of uniform microgel particles, the encapsulation and stabilization of water-in-oil hydrogel emulsions often require surfactants to reduce the surface tension of the microgel droplets. However, these surfactants must be removed with chemical demulsifiers to retrieve the cell-laden microgels for downstream applications, which often leads to toxic effects on the cells. Herein, a novel class of thermo-responsive “smart” surfactants is reported for on-demand demulsification of microfluidic droplets. These surfactants are synthesized by coupling perfluoropolyethers (PFPEs) with a thermo-responsive block of N-isopropylacrylamide (NIPAM) using reversible addition-fragmentation chain transfer (RAFT) polymerization. The resulting P(NIPAM)(n)-PFPE surfactants exhibited temperature-dependent amphiphilicity, enabling stabilization of water-in-oil droplets at low temperatures and destabilization at elevated temperatures. This approach offers a non-invasive and biocompatible method for microgel recovery without the need for harmful chemical demulsifiers or additional processing steps. The combination of precise control over surfactant properties and thermo-responsive behavior opens new avenues for developing smart, biocompatible emulsion systems for advanced droplet microfluidics applications in tissue engineering, drug delivery, and single-cell analysis.Xiangke Li, Helen Forgham, Qiuren Shen, Liwen Zhang, Christoph Meinert, Chun-Xia Zhao, Yiliang Lin, Dan Yuan, Thomas P. Davis, and Ruirui Qia
Photodegradation reveals that singlet energy transfer impedes energy-gradient-driven singlet fission in polyacene blends
No full textData source: supplementary information, https://doi.org/10.1039/D4SC06702ASinglet fission (SF) is a process that is potentially beneficial for photovoltaics by producing two triplet excitons from a single photon, but its application is often hindered by the inability to effectively separate the resultant triplet excitons. It has been proposed that an energy gradient can assist in separating triplet excitons through triplet energy transfer between chromophores of different triplet energies, but this approach has only been studied in solution and the efficacy of this strategy in the solid state is under explored. Here, we investigate energy-gradient-driven SF in a disordered solid state, in the form of suspensions of 5,12-bis(triisopropylsilylethnyl)tetracene:6,13-bis(triisopropylsilylethnyl)pentance (TIPSTn: TIPS-Pn) blend nanoparticles (NPs). Rather than using more conventional techniques such as ultrafast (sub-nanosecond) spectroscopy, we study the photophysics in these NPs through monitoring their photodegradation. TIPS-Tn photodegrades rapidly in neat NPs, but this photodegradation is suppressed upon the addition of TIPS-Pn, indicating a decrease in the TIPS-Tn triplet population. By modeling the photodegradation over a timescale of minutes to hours, we are able to reveal details of processes on the ultrafast timescale. We show that triplet energy transfer occurs from TIPS-Tn to TIPS-Pn, leading to slower photodegradation for TIPS-Tn, and faster photodegradation for TIPS-Pn. However, modeling additionally indicates that singlet energy transfer from TIPS-Tn to TIPS-Pn also occurs, and in fact acts to reduce the efficiency of TIPS-Tn SF. Hence, in this particular system, the energy gradient impedes SF, rather than assisting it. These findings indicate that chromophore pairs must be carefully selected to switch off singlet energy transfer for the energy-gradient approach to be effective in enhancing SF.Alexandra N. Stuart, Jessica M. de la Perrelle, David M. Huang, and Tak W. Ke
Characteristics and outcomes of adults with acute brain injuries admitted to intensive care units in Australia and New Zealand from 2013 to 2022
No full textBackground: The characteristics and outcomes of patients with acute brain injuries admitted to the intensive care unit (ICU) in Australia and New Zealand (ANZ) are insufficiently described. Objective: This study aimed to describe the epidemiology of acute brain injury in ICU patients in ANZ. Methods: A binational retrospective cohort study was conducted using the ANZ Intensive Care Society Adult Patient Database. Adult unplanned admissions from 2013 to 2022 were eligible unless the presence of acute brain injury could not be determined or the admission was for end-of-life care. In cases where a patient had multiple admissions, only the first was included. The population was divided into two cohorts: acute brain injury diagnoses and other diagnoses. The primary outcome was in-hospital mortality. Secondary outcomes included 90- and 180-day mortality, ICU and hospital lengths of stay, duration of invasive ventilation, and the proportion discharged home. Results: Acute brain injuries accounted for 92 948 of 684 981 unplanned ICU admissions (14%). Hypoxic ischaemic encephalopathy, traumatic brain injury, and seizures were the most common diagnoses. A total of 24 568 of 92 948 (26%) and 62 603 of 592 033 (10%) patients with acute brain injuries and other diagnoses, respectively, died in hospital. Among the patients with brain injury the highest hospital mortality was in hypoxic ischaemic encephalopathy (53%), intracerebral haemorrhage (36%), subarachnoid haemorrhage (22%), and ischaemic stroke (22%); the lowest mortality was in traumatic brain injury (14%), central nervous system infection (10%), and seizures (4%). Acute brain injury patients were more likely to receive invasive mechanical ventilation, had longer ICU and hospital lengths of stay, had higher 90- and 180-day mortality, and were more likely to be discharged to chronic care than other patients. Conclusions: Acute brain injuries accounted for a disproportionally high number of in-hospital deaths occurring in our cohort of adults who received unplanned ICU care; however, the mortality rates varied, and patients with central nervous system infections and seizures had similar or lower mortality compared to patients without brain injury.David Golding, Anis Chaba, Anthony Delaney, Valery L. Feigin, Edward Litton, Champ Mendis, Alex Poole, Andrew Udy, Paul J. Young, the Australian, New Zealand Intensive Care Society, ANZICS, Centre for Outcomes, Resource Evaluation, COR