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Search for the decay of the Higgs boson to a Z boson and a light pseudoscalar particle decaying to two photons
No full textA search for the decay of the Higgs boson to a Z boson and a light, pseudoscalar particle, a, decaying respectively to two leptons and to two photons is reported. The search uses the full LHC Run 2 proton–proton collision data at
TeV, corresponding to 139 fb−1 collected by the ATLAS detector. This is one of the first searches for this specific decay mode of the Higgs boson, and it probes unexplored parameter space in models with axion-like particles (ALPs) and extended scalar sectors. The mass of the a particle is assumed to be in the range 0.1–33 GeV. The data are analysed in two categories: a merged category where the photons from the a decay are reconstructed in the ATLAS calorimeter as a single cluster, and a resolved category in which two separate photons are detected. The main background processes are from Standard Model Z boson production in association with photons or jets. The data are in agreement with the background predictions, and upper limits on the branching ratio of the Higgs boson decay to Za times the branching ratio
are derived at the 95% confidence level and they range from 0.08% to 2% depending on the mass of the a particle. The results are also interpreted in the context of ALP models
Effectiveness and cost-effectiveness of assets-based feeding help before and after birth (ABA-feed) for improving breastfeeding initiation and continuation : protocol for a multicentre randomised controlled trial (Version 3.0)
No full textIntroduction: Breastfeeding has health benefits for infants and mothers, yet the UK has low rates with marked social inequalities. The Assets-based feeding help Before and After birth (ABA) feasibility study demonstrated the acceptability of a proactive, assets-based, woman-centred peer support intervention, inclusive of all feeding types, to mothers, peer supporters and maternity services. The ABA-feed study aims to assess the clinical and cost-effectiveness of the ABA-feed intervention compared with usual care in first-time mothers in a full trial.
Methods and analysis: A multicentre randomised controlled trial with economic evaluation to explore clinical and cost-effectiveness, and embedded process evaluation to explore differences in implementation between sites. We aim to recruit 2730 primiparous women, regardless of feeding intention. Women will be recruited at 17 sites from antenatal clinics and various remote methods including social media and invitations from midwives and health visitors. Women will be randomised at a ratio of 1.43:1 to receive either ABA-feed intervention or usual care. A train the trainer model will be used to train local Infant Feeding Coordinators to train existing peer supporters to become ‘infant feeding helpers’ in the ABA-feed intervention. Infant feeding outcomes will be collected at 3 days, and 8, 16 and 24 weeks postbirth. The primary outcome will be any breastfeeding at 8 weeks postbirth. Secondary outcomes will include breastfeeding initiation, any and exclusive breastfeeding, formula feeding practices, anxiety, social support and healthcare utilisation. All analyses will be based on the intention-to-treat principle.
Ethics and dissemination: The study protocol has been approved by the East of Scotland Research Ethics Committee. Trial results will be available through open-access publication in a peer-reviewed journal and presented at relevant meetings and conferences
The comparative performance study of the EF7 downsized engines ; fuel economy besides CO2 reduction
No full textEngine downsizing is considered a strategic idea in fuel economy enhancement as well as reduction. It is defined in the literature as the decrease in engine geometrical dimensions besides its performance being fixed. In this research, the Iranian gasoline-fueled national engine, EF7, has been investigated for 25% downsizing. After introducing the gasoline-fueled and CNG-fueled versions of downsized engines, their performance, besides release rates are studied in detail. A one-dimensional engine simulator coupled with a 3D-CFD model is developed to carry out such an investigation, an experimental test setup is provided to evaluate the accuracy of the provided numerical model, as well. The first version of presented downsized engines, called EF7, is a 3-cylinder engine with the same geometrical characteristics as the base engine, which is equipped with a turbo-charger and dual CVVT technologies. The EF7 is then introduced by fuel shifting to CNG as the second version of downsized engines, and finally, increasing the compression ratio, the EF7 is presented as the third version of studied-downsized engines. The results show almost the same rate of BSFC besides a 3.4% reduction in concentration for EF7, 20.6% fuel economy enhancement, besides 20.8% reduction in the specific release rate for EF7, and 28.8% fuel economy enhancement, besides 25.3% reduction in the specific release rate for EF7 in comparison with the base engine
Photoinitiated single-crystal to single-crystal redox transformations of titanium-oxo clusters
No full textTitanium-oxo clusters can undergo photochemical reactions under UV light, resulting in the reduction of the titanium-oxo core and oxidation of surface ligands. This is an important step in photocatalytic processes in light-absorbing Ti/O-based clusters, metal–organic frameworks, and (nano)material surfaces; however, studying the direct outcome of this photochemical process is challenging due to the fragility of the immediate photoproducts. In this report, titanium-oxo clusters [TiO(OiPr)(L)]n (n = 4, L = O2PPh2, or n = 6, L = O2CCH2tBu) undergo a two-electron photoredox reaction in the single-crystal state via an irreversible single-crystal to single-crystal (SC-SC) transformation initiated by a UV laser. The process is monitored by single crystal X-ray diffraction revealing the photoreduction of the cluster with coproduction of an (oxidized) acetone ligand, which is retained in the structure as a ligand to Ti(3+). The results demonstrate that photochemistry of inorganic molecules can be studied in the single crystal phase, allowing characterization of photoproducts which are unstable in the solution phase
Response patterns of the microbiome during hexavalent chromium remediation by Tagetes erecta L.
No full textChromium pollution, particularly hexavalent chromium [Cr(VI)], may threaten the environment and human health. This study investigated the potential of Tagetes erecta L. (Aztec marigold) for phytoremediation of soil contaminated with Cr(VI), and focused on the effects of varying concentrations of Cr(VI) on both the physicochemical properties of soil and microbiome of Tagetes erecta L. We observed that Tagetes erecta L. showed tolerance to Cr(VI) stress and maintained normal growth under these conditions, as indicated by bioconcentration factors of 0.33–0.53 in shoots and 0.39–0.70 in roots. Meanwhile, the structure and diversity of bacterial communities were significantly affected by Cr(VI) pollution. Specifically, Cr(VI) had a more significant effect on the microbial community structure in the endophytic of Tagetes erecta L. than in the rhizosphere (p < 0.05). The genera Devosia and Methylobacillus were positively correlated with Cr(VI) concentrations. Biomarkers such as Bacilli and Pseudonocardia were identified under the different Cr(VI)-contaminated treatments using LEfSe. In addition, the interaction and stability of the endophytic microbiome were enhanced under Cr(VI) stress. This study explored the interactions between heavy metals, microorganisms, and plants, providing valuable insights for developing in situ bioremediation of Cr(VI)-contaminated soils
Akratic beliefs and seemings
No full textHow does it come about that a person akratically believes that P, while at the same time believing that the available evidence speaks against that P? Among the current accounts, Scanlon offers an intuitive suggestion that one’s seeming experience that P may play an important role in the aetiology of their akratic belief that P. However, it turns out to be quite challenging to articulate what the role of seeming experience is. This paper will offer a novel development of Scanlon’s intuitive suggestion, with a focus on clear-eyed epistemic akrasia. I will argue that the primary role of seeming experience is unlikely to act as the subject’s reason or to provide the subject with prima facie justification; instead, based on the recent work in dogmatism and Cartesian clarity, I will propose a causal account, according to which, when it seems clear to the subject that P, the seeming experience may exert a brute causal force to persistently compel the subject to believe that P. This causal account also has the advantage of helping some existing accounts to explain clear-eyed epistemic akrasia
Courts, climate litigation and the evolution of earth system law
Get PDFNumerous scientific reports have evidenced the transformation of the earth system due to human activities. These changes – captured under the term ‘Anthropocene’ – require a new perspective on global law and policy. The concept of ‘earth system law’ situates law in an earth system context and offers a new perspective to interrogate the role of law in governing planetary challenges such as climate change. The discourse on earth system law has not yet fully recognised courts as actors that could shape climate governance, while climate litigation discourse has insufficiently considered aspects of earth system law. We posit that courts play an increasingly influential climate governance role and that they need to be recognised as Anthropocene institutions within the earth system law paradigm. Drawing on a set of prominent climate cases, we discuss five inter‐related domains that are relevant for earth system law and where the potential influence of courts can be discerned: establishing accountability, redefining power relations, remedying vulnerabilities and injustices, increasing the reach and impact of international climate law and applying climate science to adjudicate legal disputes. We suggest that their innovative work in these domains could provide a basis for positioning courts as planetary climate governance actors
Observation of a propagating slow magnetoacoustic wave in a coronal plasma fan with SDO/AIA and SolO/EUI
Get PDFSimultaneous observations of a propagating disturbance of EUV intensity, with SDO/AIA at 171 Å and SolO/EUI-HRIEUV at 174 Å, are investigated. The disturbance moves outwards along a plasma fan structure in active region AR 12941 on February 7th 2022, at 12:45–14:15 UT. The spacecraft line-of-sight separation is 19°. The variation of the EUV intensity resembles an almost harmonic wave with an oscillation period of
and
min for AIA and HRIEUV, respectively. Over 30 oscillation cycles are detected. The wave originated at the footpoint of the fan, anchored in a sunspot. The projected phase speeds are 60.5 ± 5.2 and 74.4 ± 6.2 km s−1 in the AIA and HRIEUV data, respectively, determined by the cross-correlation technique. The observed parameters of the propagating EUV disturbance suggest its interpretation as a slow magnetoacoustic wave. Observations with AIA show that the wave decays with height, with a calculated e-folding length of
Mm. In contrast, in the HRIEUV data, the propagating EUV disturbance is also seen much higher, with the e-folding length of
Mm. This observation demonstrates, for the first time, that the apparent spatial damping of propagating slow waves depends on the observational instrument. Moreover, our work shows that the study of slow waves can be advanced with the use of HRIEUV, and multiple instruments with non-parallel lines of sigh
TransitFit : combined multi-instrument exoplanet transit fitting for JWST, HST and ground-based transmission spectroscopy studies
Get PDFWe present TransitFit, a package designed to fit exoplanetary transit light-curves. TransitFit offers multi-epoch, multi-wavelength fitting of multi-telescope transit data. TransitFit allows per-telescope detrending to be performed simultaneously with transit parameter fitting, including custom detrending. Host limb darkening can be fitted using prior conditioning from stellar atmosphere models. We demonstrate TransitFit in a number of contexts. We model multi-telescope broadband optical data from the ground-based SPEARNET survey of the low-density hot-Neptune WASP-127 b and compare results to a previously published higher spectral resolution GTC/OSIRIS transmission spectrum. Using TransitFit, we fit 26 transit epochs by TESS to recover improved ephemeris of the hot-Jupiter WASP-91 b and a transit depth determined to a precision of 111 ppm. We use TransitFit to conduct an investigation into the contested presence of TTV signatures in WASP-126 b using 180 transits observed by TESS, concluding that there is no statistically significant evidence for such signatures from observations spanning 27 TESS sectors. We fit HST observations of WASP-43 b, demonstrating how TransitFit can use custom detrending algorithms to remove complex baseline systematics. Lastly, we present a transmission spectrum of the atmosphere of WASP-96 b constructed from simultaneous fitting of JWST NIRISS Early Release Observations and archive HST WFC3 transit data. The transmission spectrum shows generally good correspondence between spectral features present in both datasets, despite very different detrending requirements
Rational circle-equivariant elliptic cohomology of CP(V)
No full textWe compute rational T-equivariant elliptic cohomology of CP(V), where T is the circle group, and CP(V) is the T-space of complex lines for a finite dimensional complex T-representation V. Starting from an elliptic curve C over the complex numbers and a coordinate data around the identity, we achieve this computation by proving that the T-equivariant elliptic cohomology theory ECT built in [Gre05], and the T2-equivariant elliptic cohomology theory ECT2 built in [Bar22] are 1xT-split. This result allows us to reduce the computation of ECT(CP(V)) to the computation of T2-elliptic cohomology of spheres of complex representations, already performed in [Bar22]