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Colloidal lead halide perovskite nanocrystals have potential for lighting applications due to their optical properties. Precise control of the nanocrystal dimensions and composition is a prerequisite for establishing practical applications. However, the rapid nature of their synthesis precludes a detailed understanding of the synthetic pathways, thereby limiting the optimisation. Here, we deduce the formation mechanisms of anisotropic lead halide perovskite nanocrystals, 1D nanorods and 2D nanoplatelets, by combining in situ X-ray scattering and photoluminescence spectroscopy. In both cases, emissive prolate nanoclusters form when the two precursor solutions are mixed. The ensuing antisolvent addition induces the divergent anisotropy: The intermediate nanoclusters are driven into a dense hexagonal mesophase, fusing to form nanorods. Contrastingly, nanoplatelets grow freely dispersed from dissolving nanoclusters, stacking subsequently in lamellar superstructures. Shape and size control of the nanocrystals are determined primarily by the antisolvent's dipole moment and Hansen hydrogen bonding parameter. Exploiting the interplay of antisolvent and organic ligands could enable more complex nanocrystal geometries in the future., (© 2024. The Author(s).)

Achieving the goal of generating all of the world's energy via renewable sources and significantly reducing the energy usage will require the development of novel, abundant, nontoxic energy conversion materials. Here, a cost-efficient and scalable continuous flow synthesis of Cs 3 Cu 2 I 5 nanocrystals is developed as a basis for the rapid advancement of novel nanomaterials. Ideal precursor solutions are obtained through a novel batch synthesis, whose product served as a benchmark for the subsequent flow synthesis. Realizing this setup enabled a reproducible fabrication of Cs 3 Cu 2 I 5 nanocrystals. The effect of volumetric flow rate and temperature on the final product's morphology and optical properties are determined, obtaining 21% quantum yield with the optimal configuration. Consequently, the size and morphology of the nanocrystals can be tuned with far more precision and in a much broader range than previously achievable. The flow setup is readily applicable to other relevant nanomaterials. It should enable a rapid determination of a material's potential and subsequently optimize its desired properties for renewable energy generation or efficient optoelectronics., (© 2024 The Author(s). Small published by Wiley‐VCH GmbH.)

We report the precise measurement of electric fields in nanostructures, and high-contrast imaging of soft matter at ultralow electron doses by transmission electron microscopy (TEM). In particular, a versatile method based on the theorem of reciprocity is introduced to enable differential phase contrast imaging and ptychography in conventional, plane-wave illumination TEM. This is realised by a series of TEM images acquired under different tilts, thereby introducing the sampling rate in reciprocal space as a tuneable parameter, in contrast to momentum-resolved scanning techniques. First, the electric field of a p-n junction in GaAs is imaged. Second, low-dose, in-focus ptychographic and DPC characterisation of Kagome pores in weakly scattering covalent organic frameworks is demonstrated by using a precessing electron beam in combination with a direct electron detector. The approach offers utmost flexibility to record relevant spatial frequencies selectively, while acquisition times and dose requirements are significantly reduced compared to the 4D-STEM counterpart., (© 2024. The Author(s).)

Background: The optimal first-line treatment in early rheumatoid arthritis (RA) is debated. We compared clinical and radiographic outcomes of active conventional therapy with each of three biological treatments with different modes of action., Methods: Investigator-initiated, randomised, blinded-assessor study. Patients with treatment-naïve early RA with moderate-severe disease activity were randomised 1:1:1:1 to methotrexate combined with (1) active conventional therapy: oral prednisolone (tapered quickly, discontinued at week 36) or sulfasalazine, hydroxychloroquine and intra-articular glucocorticoid injections in swollen joints; (2) certolizumab pegol; (3) abatacept or (4) tocilizumab. Coprimary endpoints were week 48 Clinical Disease Activity Index (CDAI) remission (CDAI ≤2.8) and change in radiographic van der Heijde-modified Sharp Score, estimated using logistic regression and analysis of covariance, adjusted for sex, anticitrullinated protein antibody status and country. Bonferroni's and Dunnet's procedures adjusted for multiple testing (significance level: 0.025)., Results: Eight hundred and twelve patients were randomised. Adjusted CDAI remission rates at week 48 were: 59.3% (abatacept), 52.3% (certolizumab), 51.9% (tocilizumab) and 39.2% (active conventional therapy). Compared with active conventional therapy, CDAI remission rates were significantly higher for abatacept (adjusted difference +20.1%, p<0.001) and certolizumab (+13.1%, p=0.021), but not for tocilizumab (+12.7%, p=0.030). Key secondary clinical outcomes were consistently better in biological groups. Radiographic progression was low, without group differences.The proportions of patients with serious adverse events were abatacept, 8.3%; certolizumab, 12.4%; tocilizumab, 9.2%; and active conventional therapy, 10.7%., Conclusions: Compared with active conventional therapy, clinical remission rates were superior for abatacept and certolizumab pegol, but not for tocilizumab. Radiographic progression was low and similar between treatments., Trial Registration Number: NCT01491815., Competing Interests: Competing interests: MØ received the study drug from BMS and UCB; research grants from Abbvie, BMS, Merck, Novartis and UCB; speaker fees from Abbvie, BMS, Celgene, Eli-Lilly, Galapagos, Gilead, Janssen, MEDAC, Merck, Novartis, Pfizer, Sandoz, and UCB; and consultancy fees from Abbvie, BMS, Celgene, Eli-Lilly, Galapagos, Gilead, Janssen, MEDAC, Merck, Novartis, Pfizer, Sandoz and UCB. RFvV received the study drug from BMS and UCB; research grants from BMS, GSK, UCB and AstraZeneca; consulting fees from AbbVie, AstraZeneca, Biogen, BMS, Galapagos, Janssen, Miltenyi, Pfizer and UCB; expert fees from AbbVie, Galapagos, GSK, Janssen, Pfizer, R-Pharma and UCB; and advisory board fees from AbbVie, AstraZeneca, Biogen, BMS, Galapagos, Janssen, Miltenyi, Pfizer and UCB. MLH received research grants from AbbVie, Biogen, BMS, Celtrion, Eli Lily, Janssen Biologics B.V., Lundbeck Foundation, MSD, Pfizer, Roche, Samsung Biopies, Sandoz and Novartis; and institution pay from Pfizer, Medac, AbbVie and Sandoz; chaired the steering committee of the Danish Rheumatology Quality Registry (DANBIO), which receives public funding from the hospital owners and funding from pharmaceutical companies; cochairs EuroSpA, which generates real-world evidence of treatment of psoriatic arthritis and axial spondylorthritis based on secondary data and is partly funded by Novartis. DCN received consulting fees from AbbVie, BMS, Lilly, MSD, Novartis, Pfizer, Roche and UCB' meeting support from Pfizer; advisory board participation fee from Novartis; and other service fee by BMS. MTN received research grants from AbbVie, BMS, Pfizer, Galapagos, Amgen and Eli Lily. BG received consulting fee from Novartis and honorary lecture payment from Novartis and Nordic-Pharma. IG received royalty fee for book authorship and support for attending meetings by EULAR. DG received advisory board fee from Eli Lily and AbbVie and speakers fee from Eli Lily. A-BA received speakers fee from AbbVie, Eli Lily, Novartis and Pfizer. CG received the study drug from BMS and UCB. MKL received advisory board fee from AbbVie. AS received advisory board fee from GSK (institution pay). LU received speakers fee from Janssen and support for meeting/travel from AbbVie and Eli Lily. DJS received honorarium fee from UCB (not a part of this, unrelated medication). GB received consultancy fee from UCB. ICO received research grants from EU Horizon 2020 and EU Horizon Europe, advisory board participation from IMPRESS-Norway, ALPHA2PREVENT, FLECAPRO and EVOLVD, and meeting/travel support from European Clinical Research Infrastructure Network. The remaining authors declared no disclosures., (© Author(s) (or their employer(s)) 2023. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Temporal artery biopsy is considered the diagnostic gold standard for giant cell arteritis, despite approximately 39% of patients who are negative for the condition by biopsy subsequently being given a clinical diagnosis of giant cell arteritis. We aimed to assess the diagnostic accuracy of ultrasound examination in patients with suspected giant cell arteritis., Methods: In this prospective, multicentre, non-interventional, cohort study (evaluation of ultrasound's role in patients suspected of having extracranial and cranial giant cell arteritis; EUREKA), we consecutively recruited patients aged 50 years or older, with clinically suspected giant cell arteritis from three Danish hospitals (South West Jutland Hospital in Esbjerg, Silkeborg Regional Hospital, and Rigshospitalet, Glostrup). Participants had a bilateral ultrasound of the temporal, facial, common carotid, and axillary arteries. Ultrasounds were done by ultrasonographers who were systematically trained in vascular ultrasound using appropriate equipment and settings. Participants then had a temporal artery biopsy within 7 days of initiation of corticosteroid treatment. A blinded ultrasound expert assessed all ultrasound images. Ultrasound vasculitis was defined in cranial arteries as a homogeneous, hypoechoic, intimamedia complex thickness and a positive compression sign and as a homogeneous intimamedia complex of 1 mm in thickness or wider in the axillary arteries and of 1·5 mm thickness or wider in the common carotid artery. Participants were followed up at 6 months. During this 6 month period, clinicians were able to collect data from all clinical examinations to enable a full clinical diagnosis at 6 months. Clinical diagnosis was based on the expert opinion of the treating rheumatologist. The diagnostic criterion standard was diagnosis confirmed after 6 months of follow-up. We used logistic regression analyses to calculate the odds ratio and 95% CI of ultrasound as a predictor for giant cell arteritis., Findings: Between April 1, 2014, and July 31, 2017, 118 patients were screened for inclusion, of whom 106 had both ultrasound examinations and an eligible temporal artery biopsy and were included in the intention-to-diagnose population. The mean age was 72·7 years (SD 7·9), 63 (59%) participants were women, and 43 (41%) were men. Temporal artery biopsy was positive in 46 (43%) of 106 patients, and 62 (58%) of 106 patients had a clinically confirmed diagnosis of giant cell arteritis at 6 months (temporal artery biopsy sensitivity 74% [95% CI 62-84], specificity 100% [95% CI 92-100]). Cranial artery ultrasound was positive in all patients who had a positive temporal artery biopsy, and seven (58%) of 12 patients who were positive by ultrasound and negative by temporal artery biopsy were confirmed to have large-vessel giant cell arteritis via other imaging methods. The sensitivity of ultrasound diagnosis of giant cell arteritis was 94% (84-98) and specificity was 84% (70-93). Logistic regression analysis confirmed that ultrasound was the strongest baseline predictor for a clinically confirmed diagnosis of giant cell arteritis at 6 months (crude odds ratio 76·6 [95% CI 21·0-280·0]; adjusted for sex and age 141·0 [27·0-743·0])., Interpretation: Vascular ultrasound might effectively replace temporal artery biopsy as a first-line diagnostic method in patients suspected of having giant cell arteritis when done by systematically trained ultrasonographers using appropriate equipment and settings., Funding: The Institute for Regional Research at Hospital of Southwest Jutland, Esbjerg, Denmark., Competing Interests: Declaration of interests We declare no competing interests., (Copyright © 2021 Elsevier Ltd. All rights reserved.)