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Euclid preparation: LXXXV. Toward a DR1 application of higher-order weak lensing statistics
(EDP Sciences, 2026) Bouchè F.; Bouchè F.; Martinet N.; Castiblanco L.; Uhlemann C.
This is the second paper in the HOWLS (higher-order weak lensing statistics) series exploring the usage of non-Gaussian statistics for cosmology inference within Euclid. With respect to our first paper, we develop a full tomographic analysis based on realistic photometric redshifts that allows us to derive Fisher forecasts in the (8, w0) plane for a Euclid-like data release 1 (DR1) setup. We find that the five higher-order statistics (HOS) that satisfy the Gaussian likelihood assumption of the Fisher formalism (one-point probability distribution function, 1-norm, peak counts, Minkowski functionals, and Betti numbers) each outperform the shear two-point correlation functions by a factor of 2.5 on the w0 forecasts, with only marginal improvement when used in combination with two-point estimators, suggesting that every HOS is able to retrieve both the non-Gaussian and Gaussian information of the matter density field. The similar performance of the different estimators is explained by a homogeneous use of multi-scale and tomographic information, optimized to lower computational costs. These results hold for the three mass mapping techniques of the Euclid pipeline, aperture mass, Kaiser-Squires, and Kaiser-Squires plus, and they are unaffected by the application of realistic star masks. Finally, we explored the use of HOS with the Bernardeau-Nishimichi-Taruya (BNT) nulling scheme approach, finding promising results toward applying physical scale cuts to HOS.
Euclid: VI. NISP-P optical ghosts
(EDP Sciences, 2026) Schirmer M.; Schirmer M.; Okumura K.; Venemans B.; Jahnke K.
The Near-Infrared Spectrometer and Photometer (NISP) on board Euclid includes several optical elements in its path that introduce artefacts into the data from non-nominal light paths. To ensure uncontaminated source photometry, these artefacts must be accurately accounted for. This paper focuses on two specific optical features in NISP's photometric data (NISP-P): ghosts caused by the telescope's dichroic beamsplitter, and the bandpass filters within the NISP fore-optics. Both ghost types exhibit a characteristic morphology and are offset from the originating stars. The offsets are well modelled using 2D polynomials; only stars brighter than approximately 10 magnitudes in each filter produce significant ghost contributions. The masking radii for these ghosts depend on both the source-star brightness and the filter wavelength, ranging from 20 to 40 pixels. We present the final relations and models used in the near-infrared (NIR) processing function (PF) to mask these ghosts for Euclid's Quick Data Release (Q1).
Semantic coherence in noun class assignment: an experimental investigation of isiXhosa
(Open Library of Humanities, 2026) Jonas, Khanyiso; Berghoff, Robyn; Stockall, Linnaea
A central question in research on grammatical gender is whether it is semantically meaningful. This paper employs an auditory lexical decision task to investigate the role of noun class (NC) semantic coherence in judgments of novel NC marker + noun stem combinations in isiXhosa. Ninety participants made lexical decisions to pseudowords created by placing an NC prefix from a more (NC4) and less (NC10) semantically coherent NC on noun stems belonging to another class (“semantic violation items”). Responses to these pseudowords were compared to another condition in which the NC prefix was placed on a verb stem (“syntactic violation items”). While NC4 pseudowords were rejected equally robustly in the syntactic and semantic violation conditions, responses in the two conditions differed significantly for NC10, where rejection rates were lower for putative semantic violation items than syntactic violation items. These results are consistent with the hypothesis that some noun classes are associated with semantic generalisations while others are not.
School health initiatives in low-income and middle-income countries: a scoping review protocol
(BMJ Publishing Group, 2026) Hibusu, Ladislas; Mianda, Solange; Akintola, Olagoke
Background: Schools are key settings for implementing school health initiatives to prevent health problems facing learners. Initiatives exist to help learners build health literacy, adopt positive behaviours and improve their health and academic outcomes. Yet, school health outcomes have not been achieved in many settings, particularly in low-income and middle-income countries. This failure is attributed to mismatches between the initiatives and the problems being addressed, or the ill implementation of school health initiatives. Mapping these initiatives to school health problems and other school health characteristics is essential to fully understand and achieve the desired school health outcomes.Methods and analysisThis study will map literature on school health initiatives with other characteristics from 2013 to 2025. We will search articles in PubMed, Scopus, Web of Science and Google Scholar databases. Two reviewers will independently screen records and chart data; disagreements will be resolved by consensus and, when needed, adjudicated by a third reviewer. Analysis will include a qualitative review of key concepts in school health and a quantitative analysis of all included studies based on the main text categories and themes from the qualitative phase.Ethics and disseminationEthics approval is not required because this study is a scoping review of published literature and does not involve human participants. The results will be published as an article in a peer-reviewed journal and presented to stakeholders involved in implementing school health initiatives.
Nurses’ perceptions of obstacles to treatment adherence counselling for individuals with coinfections of HIV and TB in Cape Town metropolitan community health centres
(John Wiley and Sons Ltd, 2026) Ticha, Victoire; Bimerew, Million; Phetlhu, Deliwe Rene
One out of every three HIV-related deaths occurs in people who are coinfected with TB. To improve health outcomes, people coinfected with HIV and TB should continue to practice two crucial behaviours: staying in care and taking their medications as prescribed. Barriers to TB and HIV treatment adherence counselling as a tool to strengthen holistic care. However, the literature lacks an in-depth exploration of nurses’ perspectives on the perceived obstacles to treatment adherence counselling for individuals with HIV and TB coinfection in Cape Town metropolitan community health centres. The Social Cognitive Theory underpinned this study. The study investigated the perceived obstacles that nurses in community health centres in the Cape Town metropolitan region faced when providing treatment adherence counselling to patients coinfected with HIV and TB. Using a qualitative exploratory study design, nurses caring for people living with HIV and with TB were purposively selected. Semistructured interviews were used to collect data. All interviews were audio-recordedusing a digital voice recorder with participants’ permission, and verbatim transcripts were produced. We used ATLAS.ti 8 electronic software to manage the qualitative data, which were analysed thematically. Findings: Health system barriers, which included human resource constraints, increased workload, time and space limitations, unsupportive attitudes from nursing staff, inadequate capacity building, and absence of regular updates on HIV and TB adherence counselling. Patient-related barriers: Patients experienced pill burden and adverse medication side effects, and the negative impact of social grants on treatment adherence. Community-related barriers: Stigma and discrimination from the community towards people living with HIV coinfected with TB, limited knowledge among some patients, sharing of medication and substance use, and lack of community-level interaction with healthcare workers, including nurses, are the contributing factors to poor adherence counselling.