Evidence of reduced surface electron-phonon scattering in the conduction band of Bi_{2}Se_{3} by non-equilibrium ARPES

The nature of the Dirac quasiparticles in topological insulators calls for a direct investigation of the electron-phonon scattering at the \emph{surface}. By comparing time-resolved ARPES measurements of the TI Bi_{2}Se_{3} with different probing depths we show that the relaxation dynamics of the electronic temperature of the conduction band is much slower at the surface than in the bulk. This observation suggests that surface phonons are less effective in cooling the electron gas in the conduction band.Comment: 5 pages, 3 figure

Nouveaux modèles paramétriques 3-D

- Le travail présenté dans cet article se situe dans le cadre de la modélisation paramétrique des champs stochastiques tridimensionnels (3-D). Nous introduisons des modèles paramétriques issus de la décomposition de Wold 3-D et mettrons en évidence la structure spatiale et spectrale de la partie évanescente d'une texture 3-D

The Clinical Impact of [68Ga]‐DOTATATE PET/CT for the Diagnosis and Management of Ectopic Adrenocorticotropic Hormone – Secreting Tumours

ObjectivesLocalization of ectopic ACTH‐secreting tumours causing Cushing syndrome (ECS) is essential for clinical management, yet often difficult. [68Ga]‐DOTATATE PET/CT ([68Ga]‐DOTA‐(Tyr3)‐octreotate)] is an FDA‐approved high‐resolution diagnostic tool for imaging neuroendocrine tumours. Data on the clinical utility of [68Ga]‐DOTATATE in patients with ECS, however, are scarce. The objectives of this study were to determine the efficacy for ECS localization and the clinical benefit of [68Ga]‐DOTATATE imaging.MethodWe conducted a retrospective review of all cases with ECS evaluated with [68Ga]‐DOTATATE from November 2016 through October 2018 at three referral centres. The clinical benefit of [68Ga]‐DOTATATE was based on detection of new tumours and resultant changes in management.ResultsOver the study period, 28 patients with ECS underwent [68Ga]‐DOTATATE: 17 for identification of the primary tumour and 11 during follow‐up. [68Ga]‐DOTATATE identified the suspected primary ECS in 11/17 patients (65%). Of these, nine patients underwent surgery: eight with confirmed ECS (5 bronchial, 1 thymic, 1 pancreatic and 1 metastatic neuroendocrine tumour of unknown primary origin) and one patient with a false‐positive scan (adrenal gland). Of the 11 patients with ECS who underwent [68Ga]‐DOTATATE evaluation during follow‐up, the study led to changes in clinical management in 7/11 (64%) patients.Conclusions[68Ga]‐DOTATATE is sensitive in detecting primary and metastatic ECS, often identifies occult tumours after conventional imaging, and impacts clinical care in the majority of patients.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/150507/1/cen14008.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/150507/2/cen14008_am.pd

Introducing pinhole magnification by selective etching: Application to poly-Si on ultra-thin silicon oxide films

Carrier selective junctions formed by polycrystalline silicon (poly-Si) on ultra-thin silicon oxide films are currently in the spotlight of silicon photovoltaics. We develop a simple method using selective etching and conventional optical microscopy to determine the pinhole density in interfacial oxide films of poly-Si on oxide (POLO)-junctions with excellent electrical properties. We characterize the selective etching of poly-Si versus ultra-thin silicon oxide. We use test structures with deliberately patterned openings and 3 nm thin oxide films to check the feasibility of magnification by undercutting the interfacial oxide. With the successful proof of our concept we introduce a new method to access the density of nanometer-size pinholes in POLO-junctions with excellent passivation properties

Climate action for health and wellbeing in cities: a protocol for the systematic development of a database of peer-reviewed studies using machine learning methods [version 1; peer review: awaiting peer review]

Home Browse Climate action for health and wellbeing in cities: a protocol for... ALL METRICS 99 VIEWS 11 DOWNLOADS Get PDF Get XML Cite Export Track Email Share ▬ STUDY PROTOCOL Climate action for health and wellbeing in cities: a protocol for the systematic development of a database of peer-reviewed studies using machine learning methods [version 1; peer review: awaiting peer review] Kristine Belesova https://orcid.org/0000-0002-6160-50411, Max Callaghan https://orcid.org/0000-0001-8292-87582, Jan C Minx https://orcid.org/0000-0002-2862-01782, Felix Creutzig2, Catalina Turcu https://orcid.org/0000-0003-2663-25863, Emma Hutchinson1, James Milner1, Melanie Crane https://orcid.org/0000-0002-3058-22114, Andy Haines https://orcid.org/0000-0002-8053-46051, Michael Davies5, Paul Wilkinson1 Author details 1 Department of Public Health, Environments and Society and Centre on Climate Change and Planetary Health, London School of Hygiene and Tropical Medicine, London, WC1H 9SH, UK 2 Mercator Research Institute on Global Commons and Climate Change, Berlin, 10829, Germany 3 Bartlett School of Planning, University College London, London, WC1H 0QB, UK 4 Charles Perkins Centre, Sydney School of Public Health, University of Sydney, Sydney, Australia 5 Bartlett School Environment, Energy & Resources, University College London, London, WC1H 0QB, UK Kristine Belesova Roles: Conceptualization, Data Curation, Investigation, Methodology, Supervision, Writing – Original Draft Preparation, Writing – Review & Editing Max Callaghan Roles: Data Curation, Investigation, Methodology, Software, Writing – Review & Editing Jan C Minx Roles: Conceptualization, Investigation, Methodology, Software, Writing – Review & Editing Felix Creutzig Roles: Conceptualization, Investigation, Methodology, Software, Writing – Review & Editing Catalina Turcu Roles: Investigation, Methodology, Writing – Review & Editing Emma Hutchinson Roles: Investigation, Methodology, Writing – Review & Editing James Milner Roles: Methodology, Writing – Review & Editing Melanie Crane Roles: Methodology, Writing – Review & Editing Andy Haines Roles: Conceptualization, Funding Acquisition, Methodology, Supervision, Writing – Review & Editing Michael Davies Roles: Conceptualization, Funding Acquisition, Methodology, Writing – Review & Editing Paul Wilkinson Roles: Conceptualization, Funding Acquisition, Methodology, Supervision, Writing – Review & Editing Abstract Cities produce more than 70% of global greenhouse gas emissions. Action by cities is therefore crucial for climate change mitigation as well as for safeguarding the health and wellbeing of their populations under climate change. Many city governments have made ambitious commitments to climate change mitigation and adaptation and implemented a range of actions to address them. However, a systematic record and synthesis of the findings of evaluations of the effect of such actions on human health and wellbeing is currently lacking. This, in turn, impedes the development of robust knowledge on what constitutes high-impact climate actions of benefit to human health and wellbeing, which can inform future action plans, their implementation and scale-up. The development of a systematic record of studies reporting climate and health actions in cities is made challenging by the broad landscape of relevant literature scattered across many disciplines and sectors, which is challenging to effectively consolidate using traditional literature review methods. This protocol reports an innovative approach for the systematic development of a database of studies of climate change mitigation and adaptation actions implemented in cities, and their benefits (or disbenefits) for human health and wellbeing, derived from peer-reviewed academic literature. Our approach draws on extensive tailored search strategies and machine learning methods for article classification and tagging to generate a database for subsequent systematic reviews addressing questions of importance to urban decision-makers on climate actions in cities for human health and wellbeing

Possible observation of parametrically amplified coherent phasons in K0.3MoO3 using time-resolved extreme-ultraviolet ARPES

We use time- and angle-resolved photoemission spectroscopy (tr-ARPES) in the Extreme Ultraviolet (EUV) to measure the time- and momentum-dependent electronic structure of photo-excited K0.3MoO3. Prompt depletion of the Charge Density Wave (CDW) condensate launches coherent oscillations of the amplitude mode, observed as a 1.7-THz-frequency modulation of the bonding band position. In contrast, the anti-bonding band oscillates at about half this frequency. We attribute these oscillations to coherent excitation of phasons via parametric amplification of phase fluctuations.Comment: 4 figure

Selection of elms tolerant to Dutch elm Disease in south-west Romania

Ophoiostoma novo- ulmi continues to be one of the most dangerous invasive fungi, destroying many autochthonous elm forests and cultures throughout the world. Searching for natural genotypes tolerant to Dutch Elm Disease (DED) is one of the main objectives of silviculturists all over the northern hemisphere in order to save the susceptible elms and to restore their ecosystem biodiversity. In this regard, the first trial was established between 1991 and 1994, in south-west Romania (Padurea Verde, Timis, oara), using three elm species (Ulmus minor, U. glabra, and U. laevis) with 38 provenances. A local strain of Ophiostoma novo-ulmi was used to artificially inoculate all elm variants and the DED evolution was observed. Furthermore, in 2018–2021 the trial was inventoried to understand the local genotype reaction to DED in the local environmental conditions after almost 30 years. The outcomes of the present study proved the continuous presence of the infections in the comparative culture and its proximity, but the identified pathogen had a new hybrid form (found for the first time in Romania) between O. novo-ulmi ssp. Americana x O. novo-ulmi ssp. novo-ulmi. Wych elm (U. glabra) was extremely sensitive to DED: only 12 trees (out of 69 found in 2018) survived in 2021, and only one tree could be selected according to the adopted health criteria (resistance and vigour). The field elm (U. minor) was sensitive to the pathogen, but there were still individuals that showed good health status and growth. In contrast, the European white elm (U. laevis) proved constant tolerance to DED: only 15% had been found dead or presented severe symptoms of dieback. Overall, the results of this study report the diverse reactions of the Romanian regional elm genotypes to DED over the last three decades, providing promising perspectives for improving the presence of elms in the forest ecosystems of the Carpathian basin