Spin and orbital moments of ultra-thin Fe films on various semiconductor surfaces

The magnetic moments of ultrathin Fe films on three different III-V semiconductor substrates, namely GaAs, InAs and In0.2Ga0.8As have been measured with X-ray magnetic circular dichroism at room temperature to assess their relative merits as combinations suitable for next-generation spintronic devices. The results revealed rather similar spin moments and orbital moments for the three systems, suggesting the relationship between film and semiconductor lattice parameters to be less critical to magnetic moments than magnetic anisotropy

Factors controlling the net ecosystem production of cryoconite on Western Himalayan glaciers

Ikke OAIn situ experiments were conducted to determine the net ecosystem production (NEP) in cryoconite holes from the surface of two glaciers (Patsio glacier and Chhota Shigri glacier) in the Western Himalaya during the melt season from August to September 2019. The study aimed to gain an insight into the factors controlling microbial activity on glacier surfaces in this region. A wide range of parameters, including sediment thickness, TOC %, TN %, chlorophyll-a concentration, altitudinal position, and grain size of the cryoconite mineral particles were considered as potential controlling factors. From redundancy analysis, the rate of Respiration observed in cryoconite at Chhota Shigri glacier was predominantly explained by sediment thickness in cryoconite holes (37.1% of the total variance, p < 0.05) with Photosynthesis largely explained by the chlorophyll-a content of the sediment (39.6%, p < 0.05). NEP was explained primarily by the TOC content and sediment thickness in cryoconite holes (35.8% and 22.1% respectively, p < 0.05). The altitudinal position of the cryoconite is strongly correlated with biological activity, suggesting that the stability of cryoconite holes was an important factor driving primary productivity and respiration rate on the surface of Chhota Shigri glacier. We calculated that the number of melt seasons required to accumulate organic carbon in thin sediment layers (< 0.3 cm), based on our measured NEP rates, ranged from 11 to 70 years, indicating that the organic carbon in cryoconite holes largely derives from allochthonous inputs, such as elsewhere on the glacier surface. Phototrophic biomass in the same thin sediment layer of cryoconite was estimated to take atleast 4 months to be produced in situ (with mean estimated time upto 1.7 ± 1.5 years). Organic matter accumulated inside the cryoconite holes both through allochthonous deposition and via biological activity on the glacier surface in these areas may have the potential to export dissolved organic matter and associated nutrients to downstream ecosystems. Given the importance of Himalayan glaciers as a vital water source for millions of people downstream, this study highlights the need for further investigation in aspects of the quantification of in situ produced organic matter and its impact on supraglacial melting in the Himalay

Nanoscale synchrotron x-ray analysis of intranuclear iron in melanised neurons of Parkinson\u27s substantia nigra

\ua9 The Author(s) 2024. Neuromelanin-pigmented neurons of the substantia nigra are selectively lost during the progression of Parkinson’s disease. These neurons accumulate iron in the disease state, and iron-mediated neuron damage is implicated in cell death. Animal models of Parkinson’s have evidenced iron loading inside the nucleoli of nigral neurons, however the nature of intranuclear iron deposition in the melanised neurons of the human substantia nigra is not understood. Here, scanning transmission x-ray microscopy (STXM) is used to probe iron foci in relation to the surrounding ultrastructure in melanised neurons of human substantia nigra from a confirmed Parkinson’s case. In addition to the expected neuromelanin-bound iron, iron deposits are also associated with the edge of the cell nucleolus. Speciation analysis confirms these deposits to be ferric (Fe3+) iron. The function of intranuclear iron in these cells remains unresolved, although both damaging and protective mechanisms are considered. This finding shows that STXM is a powerful label-free tool for the in situ, nanoscale chemical characterisation of both organic and inorganic intracellular components. Future applications are likely to shed new light on incompletely understood biochemical mechanisms, such as metal dysregulation and morphological changes to cell nucleoli, that are important in understanding the pathogenesis of Parkinson’s

Interface alloying effects in the magnetic properties of Fe nanoislands capped with different materials

We show that Fe nanoislands capped with Al, Pd, and Pt protecting layers include an alloy at the interface with the capping layer, which explains the previously known capping layer dependence on the interparticle magnetic coupling. Vibrating sample magnetometry results, for instance, are evidencing a reduction in the magnetization measured under a magnetic field of 15 mT, which is larger in the case of the Al capping and which is due to the presence of a magnetically dead interface alloy. This reduction is also observed at the atomic level using x-ray magnetic circular dichroism measurements, showing a capping layer dependence of the Fe magnetic-moment reduction that is similar for the Pd and Pt capping, and stronger for the Al capping. The trend in the magnetic properties as a function of the capping layer is explained in the light of x-ray photoemission spectroscopy results that evidence the formation of alloys at the interface between the Fe nanoislands and the capping layers. The present results highlight the strong influence of interface alloying in systems of reduced dimensionality. In particular, it is shown that the magnetic properties are strongly affected at both the atomic and macroscopic level

How mobile are protons in the structure of dental glass ionomer cements?

The development of dental materials with improved properties and increased longevity can save costs and minimize discomfort for patients. Due to their good biocompatibility, glass ionomer cements are an interesting restorative option. However, these cements have limited mechanical strength to survive in the challenging oral environment. Therefore, a better understanding of the structure and hydration process of these cements can bring the necessary understanding to further developments. Neutrons and X-rays have been used to investigate the highly complex pore structure, as well as to assess the hydrogen mobility within these cements. Our findings suggest that the lower mechanical strength in glass ionomer cements results not only from the presence of pores, but also from the increased hydrogen mobility within the material. The relationship between microstructure, hydrogen mobility and strength brings insights into the material's durability, also demonstrating the need and opening the possibility for further research in these dental cements

Spin dynamics in bulk MnNiGa and Mn1.4Pt0.9Pd0.1Sn investigated by muon spin relaxation

Martin Gleghorn Repository Coordinator Durham University | University Library and Collections | Bill Bryson Library | Stockton Road | Durham | DH1 3LY T: +44 (0)191 334 1584 [I'm currently working remotely and am not contactable by phone] E: [email protected] | www.durham.ac.uk/library The information in this e-mail and any attachments is confidential. It is intended solely for the addressee or addressees. If you are not the intended recipient please delete the message and any attachments and notify the sender of misdelivery. Any use or disclosure of the contents of either is unauthorised and may be unlawful. This e-mail has been created in the knowledge that Internet e-mail is not a 100% secure communications medium. We advise that you understand and observe this lack of security when e-mailing us. Although steps have been taken to ensure that this e-mail and any attachments are free from any virus, we advise that in keeping with good computing practice the recipient should ensure they are actually virus free. All liability for viruses is excluded to the fullest extent permitted by law

Glossary of methods and terms used in analytical spectroscopy (IUPAC Recommendations 2019)

Recommendations are given concerning the terminology of concepts and methods used in spectroscopy in analytical chemistry, covering nuclear magnetic resonance spectroscopy, atomic spectroscopy, and vibrational spectroscopy. © 2021 IUPAC and De Gruyter. This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License. For more information, please visit: http://creativecommons.org/licenses/by-nc-nd/4.0/ 2021

Reporting quality of published reviews of commercial and publicly available mobile health apps (mHealth app reviews): A scoping review protocol

\ua9 Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY. Published by BMJ.Introduction Reviews of commercial and publicly available smartphone (mobile) health applications (mHealth app reviews) are being undertaken and published. However, there is variation in the conduct and reporting of mHealth app reviews, with no existing reporting guidelines. Building on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we aim to develop the Consensus for APP Review Reporting Items (CAPPRRI) guidance, to support the conduct and reporting of mHealth app reviews. This scoping review of published mHealth app reviews will explore their alignment, deviation, and modification to the PRISMA 2020 items for systematic reviews and identify a list of possible items to include in CAPPRRI. Method and analysis We are following the Joanna Briggs Institute approach and Arksey and O\u27Malley\u27s five-step process. Patient and public contributors, mHealth app review, digital health research and evidence synthesis experts, healthcare professionals and a specialist librarian gave feedback on the methods. We will search SCOPUS, CINAHL Plus, AMED, EMBASE, Medline, APA PsycINFO and the ACM Digital Library for articles reporting mHealth app reviews and use a two-step screening process to identify eligible articles. Information on whether the authors have reported, or how they have modified the PRISMA 2020 items in their reporting, will be extracted. Data extraction will also include the article characteristics, protocol and registration information, review question frameworks used, information about the search and screening process, how apps have been evaluated and evidence of stakeholder engagement. This will be analysed using a content synthesis approach and presented using descriptive statistics and summaries. This protocol is registered on OSF (https://osf.io/5ahjx). Ethics and dissemination Ethical approval is not required. The findings will be disseminated through peer-reviewed journal publications (shared on our project website and on the EQUATOR Network website where the CAPPRRI guidance has been registered as under development), conference presentations and blog and social media posts in lay language