Abstract
X-ray detection limit and sensitivity are important figure of merits for perovskite X-ray detectors, but literatures lack a valid mathematic expression for determining the lower limit of ...detection for a perovskite X-ray detector. In this work, we present a thorough analysis and new method for X-ray detection limit determination based on a statistical model that correlates the dark current and the X-ray induced photocurrent with the detection limit. The detection limit can be calculated through the measurement of dark current and sensitivity with an easy-to-follow practice. Alternatively, the detection limit may also be obtained by the measurement of dark current and photocurrent when repeatedly lowering the X-ray dose rate. While the material quality is critical, we show that the device architecture and working mode also have a significant influence on the sensitivity and the detection limit. Our work establishes a fair comparison metrics for material and detector development.
This paper is a review of the International Reference Ionosphere (IRI) project and model. IRI is recognized as the official standard for the Earth's ionosphere by the International Standardization ...Organization, the International Union of Radio Science, the Committee on Space Research, and the European Cooperation for Space Standardization. As requested by these organizations, IRI is an empirical (data‐based) model representing the primary ionospheric parameters based on the long data record that exists from ground and space observations of the ionosphere. The core model describes monthly averages of the electron density, electron temperature, ion temperature, and ion composition globally in the altitude range from 60 to 2,000 km. Over time additional parameters were added in response to requests from the user community, this includes the equatorial ion drift, the occurrence probability of spread‐F and of an F1 layer, auroral boundaries and the electron content from the bottom of the ionosphere to user‐specified altitude. IRI has undergone extensive validations and is used for a wide range of applications in science, engineering, and education. This review is the result of many requests we have received for a comprehensive description of the model. It is also meant as a guide for users who are interested in a deeper understanding of the model architecture and its mathematical formalism.
Plain Language Summary
The International Reference Ionosphere (IRI) is the international standard for Earth's ionosphere. The ionosphere is the plasma layer of electrons and ions that surrounds the Earth in the 60–2,000 km altitude range. In spite of being a very small constituent of the atmosphere, the important role of the ionosphere lies in its retarding and refractive effect on electromagnetic waves and in particular radio waves in the different frequency bands from very low frequencies (VLFs) to very high frequencies (VHFs). Because of these effects, IRI is needed and has been used for a wide area of applications including spacecraft navigation, telecommunication, radio astronomy, Earth observation from space, visualizations of geo‐space for educational purposes, design of satellites and their payloads, testing data analysis schemes. To support the scientific understanding and operational use, and to explain the limitations of the model, this paper provides a much needed review and description of its scientific background and mathematical formalism.
Key Points
International Reference Ionosphere (IRI): Scientific background and mathematical formalism
Description of the latest version of the model: IRI‐2022
IRI Achievements and plans for the future
The first edition of the clinical practice guidelines for liver cirrhosis was published in 2010, and the second edition was published in 2015 by the Japanese Society of Gastroenterology (JSGE). The ...revised third edition was recently published in 2020. This version has become a joint guideline by the JSGE and the Japan Society of Hepatology (JSH). In addition to the clinical questions (CQs), background questions (BQs) are new items for basic clinical knowledge, and future research questions (FRQs) are newly added clinically important items. Concerning the clinical treatment of liver cirrhosis, new findings have been reported over the past 5 years since the second edition. In this revision, we decided to match the international standards as much as possible by referring to the latest international guidelines. Newly developed agents for various complications have also made great progress. In comparison with the latest global guidelines, such as the European Association for the Study of the Liver (EASL) and American Association for the Study of Liver Diseases (AASLD), we are introducing data based on the evidence for clinical practice in Japan. The flowchart for nutrition therapy was reviewed to be useful for daily medical care by referring to overseas guidelines. We also explain several clinically important items that have recently received focus and were not mentioned in the last editions. This digest version describes the issues related to the management of liver cirrhosis and several complications in clinical practice. The content begins with a diagnostic algorithm, the revised flowchart for nutritional therapy, and refracted ascites, which are of great importance to patients with cirrhosis. In addition to the updated antiviral therapy for hepatitis B and C liver cirrhosis, the latest treatments for non-viral cirrhosis, such as alcoholic steatohepatitis/non-alcoholic steatohepatitis (ASH/NASH) and autoimmune-related cirrhosis, are also described. It also covers the latest evidence regarding the diagnosis and treatment of liver cirrhosis complications, namely gastrointestinal bleeding, ascites, hepatorenal syndrome and acute kidney injury, hepatic encephalopathy, portal thrombus, sarcopenia, muscle cramp, thrombocytopenia, pruritus, hepatopulmonary syndrome, portopulmonary hypertension, and vitamin D deficiency, including BQ, CQ and FRQ. Finally, this guideline covers prognosis prediction and liver transplantation, especially focusing on several new findings since the last version. Since this revision is a joint guideline by both societies, the same content is published simultaneously in the official English journal of JSGE and JSH.
The clumped isotopic composition of carbonate‐derived CO2 (denoted Δ47) is a function of carbonate formation temperature and in natural samples can act as a recorder of paleoclimate, burial, or ...diagenetic conditions. The absolute abundance of heavy isotopes in the universal standards VPDB and VSMOW (defined by four parameters: R13VPDB, R17VSMOW, R18VSMOW, and λ) impact calculated Δ47 values. Here, we investigate whether use of updated and more accurate values for these parameters can remove observed interlaboratory differences in the measured T‐Δ47 relationship. Using the updated parameters, we reprocess 14 published calibration data sets measured in 11 different laboratories, representing many mineralogies, bulk compositions, sample types, reaction temperatures, and sample preparation and analysis methods. Exploiting this large composite data set (n = 1,253 sample replicates), we investigate the possibility for a “universal” clumped isotope calibration. We find that applying updated parameters improves the T‐Δ47 relationship (reduces residuals) within most labs and improves overall agreement but does not eliminate all interlaboratory differences. We reaffirm earlier findings that different mineralogies do not require different calibration equations and that cleaning procedures, method of pressure baseline correction, and mass spectrometer type do not affect interlaboratory agreement. We also present new estimates of the temperature dependence of the acid digestion fractionation for Δ47 (Δ*25‐X), based on combining reprocessed data from four studies, and new theoretical equilibrium values to be used in calculation of the empirical transfer function. Overall, we have ruled out a number of possible causes of interlaboratory disagreement in the T‐Δ47 relationship, but many more remain to be investigated.
Plain Language Summary
Measured stable and clumped isotope values are fundamentally tied to established compositions of international standard materials. When these standard compositions are updated, it impacts previously published isotope measurements such as those used to define the clumped isotope calibration relationship (the foundation for use of this isotopic proxy as a paleothermometer, recorder of burial history or past diagenetic conditions). Here we reprocess 14 published clumped isotope calibration studies using updated international standard compositions and identical data processing procedures to see if these changes would eliminate previously observed interlaboratory discrepancies in clumped isotope calibration relationships. We find that this update tightens the clumped isotope calibration relationship within most laboratories and improves overall agreement between laboratories but does not eliminate all interlaboratory differences. We also propose “best practices” for data processing and dissemination going forward. This study makes progress toward resolving discrepancies in clumped isotope calibration relationships between laboratories by eliminating a number of possible causes and moves the clumped isotope community closer toward our ultimate goal of applying this powerful new proxy routinely to exciting science questions.
Key Points
Updates to 17O correction parameters and international standard compositions affect clumped isotopic compositions
Reprocessing published calibration data using new parameters and consistent methodology slightly improves interlaboratory agreement
There is no evidence (within error) for mineral‐specific offsets in calibration equation or temperature dependence of acid digestion fractionation
Objectius: aquest article identifica models i metodologies per desenvolupar polítiques de preservació digital, especialment en la descripció de la intenció, el compromís i la responsabilitat d'una ...organització que es fa en la redacció d'aquesta política.
Metodologia: es tipifiquen mètodes per desenvolupar polítiques de preservació digital i models amb apartats descriptius per redactar polítiques de preservació digital. A continuació, s'identifiquen i es concreten coincidències funcionals en metodologies per desenvolupar polítiques de preservació digital. Per acabar, s'analitza un quadre comparatiu de models amb apartats descriptius per tal de considerar elements clau per redactar una política de preservació digital.
Resultats: els models descriptius i els mètodes de desenvolupament de polítiques de preservació digital donen prioritat a la redacció d'apartats d'àmbit declaratiu que descriuen la importància de la preservació digital des de l'àmbit que comprèn i els objectius funcionals que té, els materials que cobreix, els responsables i les autoritats que donen suport a les accions; això, a fi de consolidar un pronunciament formal d'intenció, compromís i responsabilitat com a secció introductòria i clau en la política de preservació digital.
Mycelium, as the root of fungi, is composed of filamentous strands of fine hyphae that bind discrete substrate particles into a block material. With advanced processing, dense mycelium-bound ...composites (DMCs) resembling commercial particleboards can be formed. However, their mechanical properties and performance under the working conditions of particleboards are unknown. Here, we show how weathering conditions affect the DMC stress and elastic modulus. DMC was made using Ganoderma lucidum mycelium grown on a substrate of sawdust and empty fruit bunch. The DMC was then subjected to weathering under tropical conditions over 35 days and tested under flexural, tensile, and compressive loading with reference to international standards. After exposure to specified weathering conditions, the maximum stress in flexure, tension, and compression decreased substantially. The addition of a protective coating improved the resistance of DMC to weathering conditions; however, the difference between coated and uncoated samples was only found to be statistically significant in tensile strength.
Aspirin and unfractionated heparin are often used during endovascular stroke treatment to improve reperfusion and outcomes. However, the effects and risks of anti-thrombotics for this indication are ...unknown. We therefore aimed to assess the safety and efficacy of intravenous aspirin, unfractionated heparin, both, or neither started during endovascular treatment in patients with ischaemic stroke.
We did an open-label, multicentre, randomised controlled trial with a 2 × 3 factorial design in 15 centres in the Netherlands. We enrolled adult patients (ie, ≥18 years) with ischaemic stroke due to an intracranial large-vessel occlusion in the anterior circulation in whom endovascular treatment could be initiated within 6 h of symptom onset. Eligible patients had a score of 2 or more on the National Institutes of Health Stroke Scale, and a CT or MRI ruling out intracranial haemorrhage. Randomisation was done using a web-based procedure with permuted blocks and stratified by centre. Patients were randomly assigned (1:1) to receive either periprocedural intravenous aspirin (300 mg bolus) or no aspirin, and randomly assigned (1:1:1) to receive moderate-dose unfractionated heparin (5000 IU bolus followed by 1250 IU/h for 6 h), low-dose unfractionated heparin (5000 IU bolus followed by 500 IU/h for 6 h), or no unfractionated heparin. The primary outcome was the score on the modified Rankin Scale at 90 days. Symptomatic intracranial haemorrhage was the main safety outcome. Analyses were based on intention to treat, and treatment effects were expressed as odds ratios (ORs) or common ORs, with adjustment for baseline prognostic factors. This trial is registered with the International Standard Randomised Controlled Trial Number, ISRCTN76741621.
Between Jan 22, 2018, and Jan 27, 2021, we randomly assigned 663 patients; of whom, 628 (95%) provided deferred consent or died before consent could be asked and were included in the modified intention-to-treat population. On Feb 4, 2021, after unblinding and analysis of the data, the trial steering committee permanently stopped patient recruitment and the trial was stopped for safety concerns. The risk of symptomatic intracranial haemorrhage was higher in patients allocated to receive aspirin than in those not receiving aspirin (43 14% of 310 vs 23 7% of 318; adjusted OR 1·95 95% CI 1·13–3·35) as well as in patients allocated to receive unfractionated heparin than in those not receiving unfractionated heparin (44 13% of 332 vs 22 7% of 296; 1·98 1·14–3·46). Both aspirin (adjusted common OR 0·91 95% CI 0·69–1·21) and unfractionated heparin (0·81 0·61–1·08) led to a non-significant shift towards worse modified Rankin Scale scores.
Periprocedural intravenous aspirin and unfractionated heparin during endovascular stroke treatment are both associated with an increased risk of symptomatic intracranial haemorrhage without evidence for a beneficial effect on functional outcome.
The Collaboration for New Treatments of Acute Stroke consortium, the Brain Foundation Netherlands, the Ministry of Economic Affairs, Stryker, Medtronic, Cerenovus, and the Dutch Heart Foundation.
International standards that define thermal comfort in uniform environments are based on the steady-state heat balance equation that posits 'neutrality' as the optimal occupant comfort state for ...which environments are designed. But thermal perception is more than an outcome of a deterministic, steady-state heat balance. Thermal alliesthesia is a conceptual framework to understand the hedonics of a much larger spectrum of thermal environments than the more thoroughly researched concept of thermal neutrality. At its simplest, thermal alliesthesia states that the hedonic qualities of the thermal environment are determined as much by the general thermal state of the subject as by the environment itself. A peripheral thermal stimulus that offsets or counters a thermoregulatory load-error will be pleasantly perceived and vice versa, a stimulus that exacerbates thermoregulatory load-error will feel unpleasant. The present paper elaborates the thermophysiological hypothesis of alliesthesia with a particular focus on set-point control and the origins of thermoregulatory load-error signals, and then discusses them within the broader context of thermal pleasure. Alliesthesia provides an overarching framework within which diverse and previously disconnected findings of laboratory experiments, field studies and even comfort standards spanning the last 40 years of thermal comfort research can be more coherently understood.
The International Standards for Tuberculosis Care define the essential level of care for managing patients who have or are presumed to have tuberculosis, or are at increased risk of developing the ...disease. The resources and capacity in the European Union (EU) and the European Economic Area permit higher standards of care to secure quality and timely TB diagnosis, prevention and treatment. On this basis, the European Union Standards for Tuberculosis Care (ESTC) were published in 2012 as standards specifically tailored to the EU setting. Since the publication of the ESTC, new scientific evidence has become available and, therefore, the standards were reviewed and updated.A panel of international experts, led by a writing group from the European Respiratory Society (ERS) and the European Centre for Disease Prevention and Control (ECDC), updated the ESTC on the basis of new published evidence. The underlying principles of these patient-centred standards remain unchanged. The second edition of the ESTC includes 21 standards in the areas of diagnosis, treatment, HIV and comorbidities, and public health and prevention.The ESTC target clinicians and public health workers, provide an easy-to-use resource and act as a guide through all the required activities to ensure optimal diagnosis, treatment and prevention of TB.
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