Assessment of the radiation risk at flight altitudes for an extreme solar particle storm of 774 AD

Intense solar activity can lead to an acceleration of solar energetic particles and accordingly increase in the complex radiation field at commercial aviation flight altitudes. We considered here the strongest ever reported event, namely that of 774 AD registered on the basis of cosmogenic-isotope measurements, and computed the ambient dose at aviation altitude(s). Since the spectrum of solar protons during the 774 AD event cannot be directly obtained, as a first step, we derived the spectra of the solar protons during the ground level enhancement (GLE) #5 on 23 February 1956, the strongest event observed by direct measurements, which was subsequently scaled to the size of the 774 AD event and eventually used as input to the corresponding radiation model. The GLE #5 was considered a conservative approach because it revealed the hardest-ever derived energy spectrum. The global map of the ambient dose was computed under realistic data-based reconstruction of the geomagnetic field during the 774 AD epoch, based on paleomagnetic measurements. A realistic approach on the basis of a GLE #45 on 24 October 1989 was also considered, that is by scaling an event with softer spectra and lower particle fluxes compared to the GLE #5. The altitude dependence of the event-integrated dose at altitudes from 30 kft to 50 kft (9.1–15.2 km) was also computed for both scenarios. Our study of the radiation effects during the extreme event of 774 AD gives the necessary basis to be used as a reference to assess the worst-case scenario for a specific threat, that is radiation dose at flight altitudes

GEOMAGIA50.v3: 2. A new paleomagnetic database for lake and marine sediments

Background: GEOMAGIA50.v3 for sediments is a comprehensive online database providing access to published paleomagnetic, rock magnetic, and chronological data obtained from lake and marine sediments deposited over the past 50 ka. Its objective is to catalogue data that will improve our understanding of changes in the geomagnetic field, physical environments, and climate.Findings: GEOMAGIA50.v3 for sediments builds upon the structure of the pre-existing GEOMAGIA50 database for magnetic data from archeological and volcanic materials. A strong emphasis has been placed on the storage of geochronological data, and it is the first magnetic archive that includes comprehensive radiocarbon age data from sediments. The database will be updated as new sediment data become available.Conclusions: The web-based interface for the sediment database is located at http://geomagia.gfz-potsdam.de/geomagiav3/SDquery.php webcite. This paper is a companion to Brown et al. (Earth Planets Space doi:10.1186/s40623-015-0232-0, 2015) and describes the data types, structure, and functionality of the sediment database

Clinical Significance of Minimal Residual Disease at the End of Remission Induction Therapy in Childhood Acute Lymphoblastic Leukemia

BACKGROUND: Detection of minimal residual disease (MRD) in the early phase of therapy is the most powerful predictor of relapse risk in children with acute lymphoblastic leukaemia (ALL). AIM: We aimed to determine the significance of MRD at the end of remission induction therapy in the prediction of treatment outcome in children with ALL. METHODS: Sixty-four consecutive patients aged 1-14 years with newly diagnosed ALL were enrolled in this study from January 2010 to October 2017. All patients were treated according to the ALL IC BFM 2002 protocol. MRD was detected at the end of remission induction therapy (day 33) by multiparameter 6-colour flow cytometry performed on bone marrow specimens with a sensitivity of 0.01%. RESULTS: Overall, 42.2% of patients had detectable MRD on day 33 of therapy. MRD measurements were not significantly related to presenting characteristics but were associated with a poorer blast clearance on day 8 and 15 of remission induction therapy. Patients with negative MRD status on day 33 had a 5-year event-free survival of 94.6% compared with 76.1% for those with positive MRD status (P = 0.044). CONCLUSION: MRD levels at the end of remission induction therapy measured by multiparameter flow cytometry have clinical significance in childhood ALL. High levels of MRD are strongly related to poor treatment outcome

Use of chronic lymphocytic leukemia-international prognostic index in patient risk stratification-single center experience

Background: Several prognostic factors have been identified to predict the outcome of patients with chronic lymphocytic leukemia (CLL). To predict the time to first treatment (TFT) we integrated the data of clinical and biological markers in CLL-International prognostic index (CLL-IPI). Aim of the study was the determination of the impact of CLL-IPI in prediction of TFS in CLL patents.Methods: The study was set up retrospectively and included 90 patients with CLL diagnosed and treated at the university clinic of hematology for a period of time from January 2012 to January 2020. We incorporated the data of Binet staging system, most adverse cytogenetic marker and mutational status of immunoglobulin heavy chain in CLL-IPI.Results: The statistical data of the 90 patients showed that the median TFS for low CLL-IPI (N=24), intermediate CLL-IPI (N=40), high risk CLL-IPI (N=17) and very high risk group (N=9) according to the CLL-IPI scoring system was 20.1, 17.6, 7.1 and 5.8 months, respectively. Multivariate analysis indicated that del 17p (p<0.008) was independent prognostic factors of TFS.Conclusions: CLL-IPI is a powerful risk stratification tool for CLL patients and this system has also provided treatment recommendations for different patient risk subgroups.

A Rare Case of Soft Tissue Erdheim Chester Disease: Diagnostic Dilemma and Management

BACKGROUND: Erdheim Chester disease (ECD) is a rare form of non-Langerhans histiocytosis that still presents a diagnostic and clinical dilemma. CASE PRESENTATION: We present a rare case of ECD, young 31 male with atypical localisation and soft tissue presentation and no bone involvement. He started clinical investigations due to subcutaneous tumour mass in the lumbar spine that caused severe back pain. Skin biopsy revealed ECD with Immunohistochemistry CD68+, CD10+, CD11c+, vimentin+, S100A4+. Activating BRAFV600E mutation was positive from the tumour tissue. The patient was referred to the haematology department. PET CT was performed for initial disease staging. Treatment was started with corticosteroids (methylprednisolone 0.5 mg/kg per day), and after 7 days, a significant clinical improvement was noticed in terms of pain disappearance with no need for pain killers. After two weeks, treatment with interferon Alfa (IFN-α) was started in a dose of 3 million units 3 times per week. After 4 months of interim treatment PET, CT revealed a significant reduction of the tumour mass. Therapy with IFN-α was continued, and the patient is still clinically in good condition. CONCLUSION: It can be concluded that shortening the time of diagnosis of ECD is essential in treatment outcome of this disease. Still, large studies have to confirm the best treatment of this rare condition

Correlation between IGRF2000 model and measured geomagnetic data on the territory of the Republic of Macedonia from measurements in 2003 and 2004

On the basis of the measurements carried out in 2003 and 2004 on the network of repeat stations in the Republic of Macedonia, correlation between IGRF and the 2003 model as well as the 2004 model and analysis between the models were made. It should take in consideration that the difference in altitude among repeat stations (15 points) is about 1300 meters (Galicica is at highest sea level of 1691 m and Nikolic at lowest of 300 m). During data processing, correction for altitude was not made, and measured data were corrected with the data from neighboring observatories Panagiuriste, Bulgaria, Tihany, Hungary and Aquila, Italy. The paper presents correlations between IGRF model and 2003 and 2004 model for all components of geomagnetic field. The time changes for 2003 and 2004 were also calculated

Characteristics of the Matuyama‐Brunhes Magnetic Field Reversal Based on a Global Data Compilation

Magnetic field reversals are irregular events in Earth's history when the geomagnetic field changes its polarity. Reversals are recorded by spot and continuous remanent magnetization data collected from lava flows and marine sediments, respectively. The latest field reversal, the Matuyama‐Brunhes reversal (MBR), is better covered by paleomagnetic data than prior field reversals, hence providing an opportunity to understand the physical mechanisms. Despite the quantity of data, a full understanding of the MBR is still lacking. The evolution of the MBR in time and space is explored in this work by compiling a global set of paleomagnetic data, both from sediments and volcanic rocks, which encompass the period 900–700 ka. After careful evaluation of data and dating quality, regional and global stacks of virtual axial dipole moment (VADM), virtual geomagnetic pole (VGP), and paleosecular variation index (Pi) are constructed from the sediment records using bootstrap resampling. Individual VADMs and VGPs calculated from lavas are compared to these stacks. Four phases of full‐vector field instability are observed in these stacks over the period 800–770 ka. The first three phases, observed at 800–785 ka, reflect a rapid weakening of the field coupled with low VGP latitude, after which the field returned to the reverse polarity of the Matuyama chron. The fourth phase, lasting from 780 to 770 ka, is when the field reversal process completed, such that the field entered the Brunhes normal polarity state. These findings point to a complex reversal process lasting ∼30 Kyr, with the reversal ending at ∼770 ka.Plain Language Summary: The Earth's magnetic field, or geomagnetic field, which humans and some animals use for navigation, shields us from solar and cosmic radiation. The magnetic North and South poles have repeatedly, but infrequently changed their positions over Earth's history, a phenomenon known as magnetic field reversal. During a reversal, the magnetic field intensity decreased to low levels, which could have had a detrimental impact on our planet as the magnetic shielding is diminished. The magnetic field last switched polarity from the Matuyama reverse state to the current Brunhes normal polarity in the most recent field reversal. This work used regional and global stacks of paleomagnetic sediment records with reasonable age control, to investigate the Matuyama‐Brunhes reversal. From these stacks, we find that the last field reversal took ∼30 Kyr to evolve, beginning at about 800 ka and ending at around 770 ka. Our data compilation indicates that the reversal lasted longer in records from high latitudes than low‐ to mid latitudes records, which confirms a previous suggestion that local reversal duration is latitudinal dependent.Key Points: Global characteristics of the Matuyama‐Brunhes field reversal were examined from well‐dated high‐quality lava and marine core data. The Matuyama‐Brunhes reversal started at 800 ka and the whole process lasted 30 ka. The new data compilation generally confirms longer regional reversal duration at high latitudes compared to low latitudes.Alexander von Humboldt Foundation http://dx.doi.org/10.13039/501100010956Discovery Fellowship, GFZ Potsdam, Germany.https://earthref.org/ERDA/2545

Basic model of the Geo-Database of the Republic of Macedonia

In this paper is presented the basic model of geo-database of the Republic of Macedonia. The model is based on the latest information technologies using GIS and integrated database, allowing further development and upgrading of the geo-database. I present a list of digital data and maps that will be included in the geo-database. Logical structure is shown for entering data into the database and the service architecture of applications and data redundancy