Cosmic rays’ interactions with the residual atmosphere surrounding the Earth produce a variety of particles, like electrons, positrons, protons, anti-protons, and Helium nuclei that can be observed ...below the local geomagnetic cutoff. In this work, we present new measurements of downward-going, albedo proton fluxes with kinetic energy in the range ∼40–∼250 MeV, performed by the High-Energy Particle Detector (HEPD-01) on board of the China Seismo-Electromagnetic Satellite - CSES-01 - at an altitude of ∼500 km. Employing a dedicated trajectory-tracing simulation routine, the protons collected by HEPD-01 are classified into quasi-trapped (QT), long lifetime (≳10 s) particles concentrating in the equatorial region of the Earth, and un-trapped (UT), distributed at all latitudes; the latter includes both precipitating short lifetime particles (UTS) and pseudo-trapped long lifetime (UTL) populations, abundant in the so-called penumbra regions. The temporal trend of re-entrant protons between 2018 and 2022 is also reported, assessing the stability of such population during the data-taking period of HEPD-01; this highlights their independence from the long-term modulating effect of the solar activity.
•A study of re-entrant albedo protons in the Earth’s magnetosphere as a function of energy with the HEPD-01 payload is presented.•A comparison with past experiments is carried out, with good results.•Time-profiles of re-entrant albedo protons show a general stability during the analyzed period.
JEM-EUSO is an international program for the development of space-based Ultra-High Energy Cosmic Ray observatories. The program consists of a series of missions which are either under development or ...in the data analysis phase. All instruments are based on a wide-field-of-view telescope, which operates in the near-UV range, designed to detect the fluorescence light emitted by extensive air showers in the atmosphere. We describe the simulation software ESAF in the framework of the JEM-EUSO program and explain the physical assumptions used. We present here the implementation of the JEM-EUSO, POEMMA, K-EUSO, TUS, Mini-EUSO, EUSO-SPB1 and EUSO-TA configurations in ESAF. For the first time ESAF simulation outputs are compared with experimental data.
Abstract
High-energy, long gamma-ray bursts (GRBs) can be generated by the core collapse of massive stars at the end of their lives. When they happen in the close-by universe they can be ...exceptionally bright, as seen from the Earth in the case of the recent, giant, long-lasting GRB221009A. GRB221009A was produced by a collapsing star with a redshift of 0.152: this event was observed by many gamma-ray space experiments, which also detected an extraordinary long gamma-ray afterglow. The exceptionally large fluence of the prompt emission of about 0.013 erg cm
−2
illuminated a large geographical region centered on India and including Europe and Asia. We report in this paper the observation of sudden electron flux changes correlated with GRB221009A and measured by the HEPP-L charged particle detector on board the China Seismo-Electromagnetic Satellite, which was orbiting over Europe at the time of the GRB event. The time structure of the observed electron flux closely matches the very distinctive time dependence of the photon flux associated with the main part of the emission at around 13:20 UTC on 2022 October 9. To test the origin of these signals, we set up a simplified simulation of one HEPP-L subdetector: the results of this analysis suggest that the signals observed are mostly due to electrons created within the aluminum collimator surrounding the silicon detector, providing real-time monitoring of the very intense photon fluxes. We discuss the implications of this observation for existing and forthcoming particle detectors on low Earth orbits.
Abstract
In this paper we report the detection of five strong gamma-ray bursts (GRBs) by the High-Energy Particle Detector (HEPD-01) mounted on board the China Seismo-Electromagnetic Satellite, ...operational since 2018 on a Sun-synchronous polar orbit at a ∼507 km altitude and 97° inclination. HEPD-01 was designed to detect high-energy electrons in the energy range 3–100 MeV, protons in the range 30–300 MeV, and light nuclei in the range 30–300 MeV n
−1
. Nonetheless, Monte Carlo simulations have shown HEPD-01 is sensitive to gamma-ray photons in the energy range 300 keV–50 MeV, even if with a moderate effective area above ∼5 MeV. A dedicated time correlation analysis between GRBs reported in literature and signals from a set of HEPD-01 trigger configuration masks has confirmed the anticipated detector sensitivity to high-energy photons. A comparison between the simultaneous time profiles of HEPD-01 electron fluxes and photons from GRB190114C, GRB190305A, GRB190928A, GRB200826B, and GRB211211A has shown a remarkable similarity, in spite of the different energy ranges. The high-energy response, with peak sensitivity at about 2 MeV, and moderate effective area of the detector in the actual flight configuration explain why these five GRBs, characterized by a fluence above ∼3 × 10
−5
erg cm
−2
in the energy interval 300 keV–50 MeV, have been detected.
Childhood ataxia with central nervous system hypomyelination (CACH) syndrome is an autosomal recessive transmitted leukodystrophy characterised by early childhood onset and acute deterioration ...following febrile illnesses or head trauma. We describe the case of a child with early onset of CACH syndrome. He presented with cerebellar ataxia beginning around two years of age with mild mental retardation. MRI showed diffuse white matter signal changes with thinning of the corpus callosum.
Abstract
Background
Transthyretin amyloidosis is a life-threatening disorder caused by the deposition of TTR amyloid in various tissues and organs. The most common worldwide pathogenic variant with ...almost exclusive cardiac involvement is Val122Ile (rs76992529), with an allele frequency of 3.5% in the U.S. African-American population, but rare in Caucasians. Unexpectedly, we identified 23 Caucasian individuals with Val122Ile in our amyloidosis referral center (9 affected patients, 14 carriers), belonging to 9 unrelated families.
Purpose
To determine the ancestral origin of the Tuscan founder population of TTR Val122Ile carriers.
Methods
A total of 24 individuals were included in the analysis (our 23 probands and relatives from Val122Ile families and the Caucasian reference sample NA10851 (CEU – Utah resident with European ancestry). All samples were genotyped using the EUROFORGEN Global AIM-SNP array1, inclusive of 127 highly informative SNPs to infer genetic ancestry. We have performed a principal component analysis (PCA) of the 9 unrelated probands and NA10851, compared with the Phase 3 of the 1000 Genomes Project data, comprising 2504 unrelated individuals from >20 distinct populations.(Figure 1).
Results
As shown in Figure 1, all our samples but one (from Argentina) cluster very close to the super-cluster of European populations, and distant from the populations of African ancestry. The proband from Argentina and the Caucasian reference sample NA10851 cluster close to Mexicans and Peruvians, and the super-cluster of European populations, respectively, confirming the robustness of the analysis.
Conclusion
Based on this result, we can confidently conclude that our samples from Tuscan families in which the TTR Val122Ile variant segregates are of ancestral European origin, with no mixed African ancestry, implying that the same variant originated in Africans and Europeans independently and not as result of genetic admixture. These findings suggest the presence of a mutational hot spots in TTR, with potential impact on the epidemiology of amyloidosis worldwide.
Acknowledgement/Funding
The present study was supported by an Investigator-Initiated Research to Azienda Ospedaliero Universitaria Careggi from Pfizer Srl.
Abstract
Background
Electrocardiographic (ECG) abnormalities are common in patients presenting with Light-Chain (AL) or Transthyretin (ATTR) related Cardiac Amyloidosis (CA). Type of amyloid may ...differently affect electrical properties of the heart being responsible for variable patterns of ECG anomalies at presentation.
Purpose
In this retrospective, observational study we sought to compare prevalence of ECG abnormalities between AL and ATTR patients with CA.
Methods
Clinical files from two Referral Centres were reviewed; ECG recordings were analysed by trained cardiologists and relevant findings were reported about rhythm (sinus vs atrial fibrillation AF), grade I or grade II atrio-ventricular (AV) delays, intra-ventricular (IV) conduction abnormalities, low-voltage QRS and pseudo-necrosis pattern. Presence of pace-maker (PM) and stimulated QRS were regarded to as clinical equivalents for AV block, after review of indications to implantation.
Results
Two hundred and fifty-one patients were identified (127 ATTR vs 124 AL; among ATTR, 27 patients had mutation in TTR gene: 10 Val142Ile, 11 Ile88Leu, 6 other). As expected, most ATTR patients were male (89% vs 56% in AL, p: <0.001), and AL patients were younger (mean age 64 53–70 vs 79 73–83; p: <0.001).
Pathological ECG findings were common in both subgroups, involving more than three-quarters of the overall population (82% in ATTR, vs 72% in AL, p: 0.06). Atrial fibrillation was more common in ATTR, prevailing in 39% vs 5.6% (p: <0.001). ATTR had a higher burden of AV block (53% vs 13%, p: <0.001) and IV conduction delays (43% vs 21%, p: <0.001), and consistently presented a higher prevalence of PMs (24 patients vs 1). Low-voltage QRS was more prevalent in AL patients (52% vs 28%, p: <0.001), while no significant difference was found in prevalence of pseudo-necrosis patterns (ATTR: 29%, AL: 40%; p: ns).
Due to imbalance in age and gender and relative possible confounding effect on rhythm disturbances, adjusted odds ratios (OR) were calculated. It resulted that ATTR was independently associated with a higher prevalence of AF and AV conduction delays when compared to AL (adjusted OR: 4 95% CI: 1.4–11.2, p: 0.008, and 6.2 95% CI: 2.6–14.9, p: <0.001; respectively), while being inversely associated with low-voltage QRS (adjusted OR: 0.4 95% CI: 0.2–0.9, p: 0.026).
Conclusions
ECG abnormalities are common in CA. Rhythm disturbances are more prevalent in ATTR, while AL more often results in low-voltage QRS. Such differences remain relevant after adjustment for age and gender imbalance, thus suggesting an aetiology-specific link.
Abstract
Background
Left atrial function (AEF) is a parameter of paramount importance that has a prognostic value in a number of heart conditions. Cardiac involvement in both light-chain and ...transthyretin amyloidosis is the main driver of prognosis and influences treatment strategies. Cardiac magnetic resonance (CMR) provides high quality images of the left and right atria using high temporal resolution steady state free precession (SSFP) cine sequences.
Purpose
The aim of our study was to assess by CMR left atrial function and his correlation with prognosis in patients with cardiac amyloidosis.
Method
We enrolled 80 consecutive patients with diagnosis of cardiac amyloidosis: 38 patients (47%) with light-chain and 42 patients (53%) with transthyretin one. CMR was performed using a 1.5-T scanner. In all subjects, the study of atria was obtained by acquiring cine steady-state free precession (SSFP). Left Atrial function was evaluated by the ratio between the maximum and the minimum LA volume. A median follow up of 937 days was performed and 36 patients (44%) died of cardiac causes. We evaluated cardiac death as endpoint. We split out all the patient in 4 different quartiles depending on left atrial function: in the first quartile patients with AEF≤14% that reflects severe atrial dysfunction, in the second quartile patients with AEF between 14 and 19%, in the third quartile patients with AEF between 19 and 36% and in the last one patients with AEF≥36% that represent patients with normal value of left atrial function.
Results
We found that CMR assessed left atrial function allowed to individuate and stratify the prognosis in patients with cardiac amyloidosis. The most effective parameter to evaluate cardiac death was left atrial function with a cut off ≤14% that could predict cardiac related mortality with the same accuracy in both light-chain and transthyretin amyloidosis patients. Kaplan Meier analysis showed that patients with AEF≤14% had a worse prognosis as compared to patient with AEF≥14% (log rank p. 0001). Furthermore patients with AEF≤14% have a cardiac death risk of 32% at 1 year and 61% at 3 years.
Kaplan Meier analysis
Conclusion
Cardiac magnetic resonance is an imaging modality that allows to individuate with great accuracy left atrial function in patients with various heart conditions and especially cardiac amyloidosis. CMR left atrial function assessment clearly identifies a subgroup of cardiac amyloid patients with an increased risk of death.
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