BDNF activates TrkB/PLCγ1 signaling pathway to promote proliferation and invasion of ovarian cancer cells through inhibition of apoptosis

OBJECTIVE

Abnormal expression and activation of tropomyosin-related kinase receptor B (TrkB) are observed in many pathological conditions, including many types of cancer. We try to explore the relationship between ovarian cancer and Brain-derived neurotrophic factor (BDNF), a ligand of TrkB.

MATERIALS AND METHODS

Human ovarian cancer cell line SKOV-3 was used in this study. qPCR, immunohistochemistry, and immunoblot were used to assay BDNF and TrkB expression level. Scratch assay was used to test the cell motility, and transwell assay was used to test the cell migration ability.

RESULTS

We found that BDNF promotes the proliferation and invasion of human ovarian cancer SKOV-3 cells depend on the activation of TrkB. To illuminate the downstream pathway of BDNF/TrkB, we silenced AKT1 and PLCγ1 by siRNA. The functional assay showed that activated PLCγ1 signaling pathway is necessary for the proliferation and invasion of cancer cells other than the AKT pathway. Further study showed that PLCγ1 could inhibit the apoptosis of cancer cells.

CONCLUSIONS

BDNF triggers TrkB/PLCγ1 signaling pathway to promote proliferation and invasion of ovarian cancer cells through inhibition of apoptosis.

Negative Delta-T Noise in the Fractional Quantum Hall Effect

We study the current correlations of fractional quantum Hall edges at the output of a quantum point contact subjected to a temperature gradient. This out-of-equilibrium situation gives rise to a form of temperature-activated shot noise, dubbed delta-T noise. We show that the tunneling of Laughlin quasiparticles leads to a negative delta-T noise, in stark contrast with electron tunneling. Moreover, varying the transmission of the quantum point contact or applying a voltage bias across the Hall bar may flip the sign of this noise contribution, yielding signatures that can be accessed experimentally.

Safety and efficacy of stereotactic body radiation therapy (SBRT) for the treatment of canine thyroid carcinoma

Thyroid carcinoma develops spontaneously in dogs, with only 25% to 50% of cases amenable to surgery at diagnosis. Local control for unresectable tumours can be provided with external beam radiotherapy. The aim of this retrospective study is to describe the safety and efficacy of stereotactic body radiation therapy (SBRT) for treatment of canine thyroid carcinoma. Twenty-three dogs met inclusion criteria; median tumour volume before SBRT was 129.9 cm³ (range, 2.7-452.8 cm³ ). Sixteen patients (70%) had unresectable tumours. Pulmonary metastasis was present or suspected in 10 patients (44%) before SBRT. Patients were prescribed 15 to 40 Gy to targeted tumour volume in one to five fractions. Twenty patients evaluated had overall response rate of 70% (complete response, n = 4; partial response, n = 10). Thirteen out of sixteen (81%) symptomatic patients had clinical improvement within a median time of 16 days (range, 2-79 days). Median progression free survival (MPFS) was 315 days. Median survival time (MST) was 362 days. Nine patients (39%) had grade 1 acute radiation toxicity. Three patients had grade 1 late radiation toxicity (two leukotrichia and one [4%] with intermittent cough). Responders had significantly longer MPFS (362 vs 90 days; HR 4.3; 95% CI 1.4-13.5; P = .013) and MST (455 vs 90 days; HR 2.9; 95% CI 1-8.4; P = .053). Presenting with metastasis was not a significant negative prognostic factor (MST 347 vs 348 days without metastasis; P = .352). SBRT is a safe and effective treatment modality for non-resectable canine thyroid carcinoma.

SAT0309 CARDIAC MAGNETIC RESONANCE IMAGING ELEVATED NATIVE MYOCARDIAL T1 IS PREDICTIVE FOR THE DEVELOPMENT OF MYOCARDIAL DYSFUNCTION IN SYSTEMIC SCLEROSIS

Background:

All patients included in the study fulfilled the ACR/EULAR classification criteria for SSc. We prospectively included patients who underwent at least two CMR at 1.5T, including native T1 and T2 mapping (which give account for myocardial fibrosis and myocardial edema respectively), left and right ventricles morphology and functional assessment, and Late Gadolinium Enhancement (LGE) as a part of routine follow-up between 2015 and 2019.

Objectives:

To evaluate the prognostic value of initial abnormal T1 mapping.

Methods:

All patients included in the study fulfilled the ACR/EULAR classification criteria for SSc. We prospectively included patients who underwent at least two CMR at 1.5T, including native T1 and T2 mapping (which give account for myocardial fibrosis and myocardial edema respectively), left and right ventricles morphology and functional assessment, and Late Gadolinium Enhancement (LGE) as a part of routine follow-up between 2015 and 2019.

Results:

Sixty-three patients underwent at list two CMR during the study period. Forty-three patients were women. Mean age was 52.5±15.5 years old. Follow-up duration between the initial and the follow-up CMR was 14.5±11.5 months. Forty-one had diffuse SSc. The mean native T1 was 1066.8 ±44.6 ms. Twenty-one patients suffered from cardiac clinical manifestations. Nine patients died during the follow-up. Thirty patients (47.6%) had elevated T1 (ET1) with mean T1 1105.4±36.7 ms at the time of initial CMR. Initial ET1 was clearly correlated with: 1/ alteration of Left Ventricle (LV) Ejection fraction (EF) (r=0.5, p<0.0001) during the study period, 2/LV dilatation at initial screening and follow up (r=0.22, p=0.03 and r=0.3, p=0.02). Regarding Right ventricle, initial ET1 was correlated with initial Right Ventricle (RV) dilatation (r=0.3, p=0.02) but neither with RV volume nor RVEF at follow-up. Interestingly, initial ET1 correlated with pericardial effusion (r=0.3, p=0.003) which is known to be a pejorative prognostic factor. Seventeen patients (28%) had LGE but the ET1 at initial screening and follow-up was not correlated with LGE.

Six patients had elevated T2 (ET2) which correlated with initial and follow up LV dilatation (r=0,32, p=0.002 and r=0.5, p<0.0001 respectively) but not with LVEF during the period study. Among other parameters, initial increased BNP was correlated with follow up ET1 LVEF and RVEF (r=0.4, p=0.01; r=0.35, p=0.007; r=0,37, p=0.005 respectively). In the same way, initial Pulmonary Arterial Hypertension (PAH) was correlated with follow up ET1 (r=0.3, p=0.02). Initial ET1 did not correlate with age, sex, cardiovascular risk factors, cardiac manifestations or death.

Conclusion:

Assessment of diffuse myocardial fibrosis by native T1 is predictive of the occurrence of cardiac dysfunction at the follow-up as initial ET1 was associated with decreased left ventricular function and LV and RV dilatations). These data highlights the potential role of CMR with T1mapping in initial screening and at the follow-up and provides new insights in the cardiac SSc follow up strategy.

References:

[1]Poindron V, Chatelus E, Canuet M, Gottenberg JE, Arnaud L, Gangi A, Gavand PE, Guffroy A, Korganow AS, Germain P, Sibilia J, El Ghannudi S, Martin T.T1 mapping cardiac magnetic resonance imaging frequently detects subclinical diffuse myocardial fibrosis in systemic sclerosis patients.Semin Arthritis Rheum. 2019 Jun 19.

Disclosure of Interests:

None declared

AB1049 CLINICAL SPECTRUM AND THERAPEUTIC MANAGEMENT OF AUTO-IMMUNE MYELOFIBROSIS: A NATION-WIDE STUDY OF 30 CASES

Background:

Little is known about autoimmune myelofibrosis (AIMF), a rare entity that can occur alone or in association with another autoimmune disease (AID) and is responsible for bone marrow (BM) failure and life-threatening complications.

Objectives:

We conducted a nationwide retrospective observational study of AIMF cases to better characterize the epidemiology, clinical presentation and evolution of this rare entity.

Methods:

The aim of the study was to analyze the characteristics of AIMF and the nature and indication of treatments currently used. Response to treatment was evaluated by the revised Tefferi et al. response criteria.

Results:

Among 30 cases of AIMF, the sex ratio (F/M) was 4:1 and the median age at diagnosis was 37 years (interquartile range 30–49). AIMF was diagnosed after the onset of an associated AID in 12 cases and concomitant to an AID in the remaining 18 cases. The most frequently associated AID was systemic lupus erythematous, followed by Sjögren syndrome. All cases consisted of reticulin fibers, and no collagen fibrosis was described. More than 50% of cases showed complete response after first-line therapy, with glucocorticoids (GC) in 28 cases. Half of the cases had treatment complications mainly related to GC therapy.

Conclusion:

Diagnosis of AIMF remains challenging in the absence of a validated set of diagnosis criteria, and must always be searched in the presence of hematological abnormalities at onset or during follow-up of AID. Clinical context, search for mutations and pathology findings can help differentiating this rare disease from a clonal pathology. GC is currently an effective first-choice therapy for AIMF, but a high rate of GC dependency and long-term complications indicate the need to find new sparing drugs.

Disclosure of Interests:

PHILIPPE MERTZ: None declared, Emilie Chalayer: None declared, Jean Sibilia: None declared, Jacques-Eric Gottenberg Grant/research support from: BMS, Pfizer, Consultant of: BMS, Sanofi-Genzyme, UCB, Speakers bureau: Abbvie, Eli Lilly and Co., Roche, Sanofi-Genzyme, UCB, Anne-Sophie Korganow: None declared, Laurent Arnaud: None declared, Thierry Martin: None declared

AB0510 INFLIXIMAB IS AN EFFECTIVE GLUCOCORTICOID-SPARING TREATMENT FOR TAKAYASU ARTERITIS: RESULTS OF A MULTICENTER OPEN-LABEL PROSPECTIVE STUDY

Background:

Approximately half of patients with Takayasu Arteritis (TA) have glucocorticoid (GC)-dependency and require the addition of a second-line immunosuppressive treatment.

Objectives:

Here, we conducted a multicenter open-label prospective cohort study to assess the efficacy and safety of infliximab originator as a GC-sparing agent in TA.

Methods:

A temporary recommendation for use for infliximab in refractory TA was approved by the French National Drug Authorities (April 2014). Infliximab was administered to patients in case of disease activity with a NIH score ≥2 despite conventional therapy. Data regarding patient’s clinical, laboratory, imaging and treatments were obtained at baseline, and at each following visit until last visit (October 2017). TA activity was evaluated according to NIH criteria and GC requirement throughout the study.

Results:

Twenty-three patients were enrolled, including 19 female. The median age at inclusion was 33 years (Interquartile range, IQR: 23-44 years). At baseline, 17 (74%) patients were treated with GCs, at a median dose of 10 mg/day (IQR: 0-21) of prednisone-equivalent. After a median follow-up of 36.9 months (IQR: 10-58.7), improvement of ≥1 NIH criterion of TA activity was achieved for 14/22 (64%) patients. The median GC dose was 8 mg/day (IQR: 7-10) at 6 months; 5 mg/day (IQR: 0-8) at 12 months and 0 mg/day (IQR: 0-5) at 36 months of follow-up. Overall, infliximab originator had a significant GC-sparing effect between baseline and last follow-up (p=0.009).

Conclusion:

This multicenter open-label cohort study suggests that infliximab originator is an effective GC-sparing treatment for TA refractory to conventional therapy.

Disclosure of Interests:

None declared

FRI0249 IN MYOSITIS PATIENTS, SJÖGREN’S SYNDROME IS ASSOCIATED WITH INCLUSION BODY MYOSITIS AND WITH ANTI-CN1A ANTIBODIES INDEPENDENTLY OF THE MYOSITIS SUBTYPE

Background:

Myositis are characterized by weakness and muscle inflammation. They encompass heterogeneous conditions, which include dermatomyositis (DM), inclusion body myositis (IBM) and polymyositis (PM) according to the EULAR/ACR 2017 criteria. We recently recorded a high prevalence of IBM in a cohort of primary Sjögren’s syndrome (SS) (1). The signification of SS in the setting of myositis is unanswered.

Objectives:

To refine the signification of SS in the setting of myositis.

Methods:

Among a monocentric myositis cohort (according to the EULAR/ACR 2017 criteria), SS patients (according to the ACR/EULAR 2016 criteria) were identified (myositis/SS+ group) and compared to myositis patients without SS (myositis/SS- group).

Results:

Among 414 myositis patients, SS criteria were available for 96 patients. Thirty two (33%) presented SS. Patients with SS tended to be more frequently women (F/M ratio 9.7 vs 3.0, p = 0.07). Age at diagnosis of myositis was similar in both groups (53 years [range 21-74] vs 53 years [range 16-77], p = 0.51).

Myositis subtypes repartition (as defined by EULAR/ACR 2017 criteria) was different in myositis/SS+ and myositis/SS- groups (p = 0.021), IBM being four-fold more prevalent in myositis/SS+ group (25% vs 6%, p = 0.018). Accordingly, the delay between the first muscle symptoms and myositis diagnosis was longer in myositis/SS+ group (7 months [0-336] vs 4 months [0-122], p = 0.041). Moreover, aside anti-cN1A antibodies, myositis-specific antibodies were less frequently found in myositis/SS+ patients than in myositis/SS- ones (16/32 [50%] vs 46/64 [72%], p = 0.035).

Anti-cN1A antibodies were more prevalent in myositis/SS+ patients (33% vs 5.8%, p = 0.0032). However, in myositis/SS+ group, anti-cN1A were frequent in each of the EULAR/ACR 2017 myositis subtypes and the association between SS and anti-cN1A positivity was maintained in a multivariate analysis adjusted with the diagnosis of IBM (p = 0.023).

Seven of the myositis/SS+ patients (22%) had systemic involvement typical of SS (vs 6 [9%] of the myositis/SS- patients, p = 0.12) including polyneuropathy (6 [20%] vs 6 [10%]) and type 2 cryoglobulinaemic vasculitis (1 [3%] vs 1 [1.6%]). In addition, 2 (6%) myositis/SS+ patients developed a lymphoma (one B diffuse large cell lymphoma of the parotid and one non-Hodgkin lymphoma), vs none of the myositis/SS- patients (p = 0.11). Only one (3%) of the myositis/SS+ patients developed myositis-associated cancer (diagnosed within 3 years of myositis diagnosis) versus 6 (9%) of the myositis/SS- patients (p = 0.66).

Aside hydroxychloroquine, more frequently used in myositis/SS+ group (38% vs 16%, p = 0.018), no significant difference was found in the management of the patients (taking into account the myositis subtype).

Conclusion:

Myositis patients with SS have more frequently IBM than myositis patients without SS. They also have more frequently anti-cN1A antibodies, independently of the myositis subtype. They might develop systemic complications of SS.

References:

[1]Felten R, Seror R, Vittecoq O, Hachulla E, Perdriger A, Dieude P, et al. SAT0470 Myositis, often suspected, is actually rare in primary Sjögren’s syndrome: data from the French cohort ASSESS. In BMJ Publishing Group Ltd and European League Against Rheumatism; 2018. p. 1093.1–1093. Available from:http://ard.bmj.com/lookup/doi/10.1136/annrheumdis-2018-eular.2945

Disclosure of Interests:

Dan LEVY: None declared, Benoit Nespola: None declared, Margherita Giannini: None declared, Renaud FELTEN: None declared, Coralie Varoquier: None declared, Marina Rinagel: None declared, Anne-Sophie Korganow: None declared, Vincent Poindron: None declared, Thierry Martin: None declared, Francois Maurier: None declared, Hassam Chereih: None declared, Bastien Bouldoires: None declared, Baptiste Hervier: None declared, Cédric Lenormand: None declared, Laurent Arnaud: None declared, Bernard Geny: None declared, Jean Sibilia: None declared, Jacques-Eric Gottenberg Grant/research support from: BMS, Pfizer, Consultant of: BMS, Sanofi-Genzyme, UCB, Speakers bureau: Abbvie, Eli Lilly and Co., Roche, Sanofi-Genzyme, UCB, alain meyer: None declared

Properties of Neon, Magnesium, and Silicon Primary Cosmic Rays Results from the Alpha Magnetic Spectrometer

We report the observation of new properties of primary cosmic rays, neon (Ne), magnesium (Mg), and silicon (Si), measured in the rigidity range 2.15 GV to 3.0 TV with 1.8×10^{6}  Ne, 2.2×10^{6}  Mg, and 1.6×10^{6}  Si nuclei collected by the Alpha Magnetic Spectrometer experiment on the International Space Station. The Ne and Mg spectra have identical rigidity dependence above 3.65 GV. The three spectra have identical rigidity dependence above 86.5 GV, deviate from a single power law above 200 GV, and harden in an identical way. Unexpectedly, above 86.5 GV the rigidity dependence of primary cosmic rays Ne, Mg, and Si spectra is different from the rigidity dependence of primary cosmic rays He, C, and O. This shows that the Ne, Mg, and Si and He, C, and O are two different classes of primary cosmic rays.

Nevirapine Use Is Associated with Higher Bone Mineral Density in HIV-1 Positive Subjects on Long-Term Antiretroviral Therapy

We assessed bone mineral density (BMD) in a cohort of human immunodeficiency virus (HIV)-positive patients after a median of 11 years of combination antiretroviral therapy (cART) and evaluated the respective role of HIV infection and antiretroviral drugs (ARVs). A cross-sectional study of 162 participants (131 male) from the ANRS-C08 cohort was performed with bone dual-energy X-ray absorptiometry (DXA) scans and renal assessment. The window of exposure to ARVs was defined as an exposure of more than six cumulative months during the last 3 years before the DXA evaluation to account for a cumulative exposure that could affect bone remodeling. The association with low BMD (Z-score < -2) was assessed by a multiple logistic regression model. The study population was 50 years (median), hepatitis C virus (HCV) (18%), and hepatitis B virus (HBV) (8%) coinfection with HIV-RNA <50 c/mL in 89%, median CD4 of 619/mm³. Prevalence of low BMD was 18% in males and 6% in females. The factors associated with a Z-score < -2 in males were uric acid renal loss [adjusted odds ratio (aOR): 6.1; 95% confidence interval (CI): 1.2-31.5; p = .03], HCV coinfection (aOR: 4.0; 95% CI: 1.3-12.2; p = .02), and less frequent window of exposure to nevirapine (NVP) (aOR: 0.1; 95% CI: 0.02-0.6; p = .01). For the full study sample, there was a strong positive association between duration of exposure to NVP and lumbar spine Z-score (p = .004). HIV-positive patients exposed to long-term cART have a high incidence of low BMD. Tenofovir disoproxil fumarate and ritonavir-boosted protease inhibitors did not seem to be associated with increased risk of low BMD, whereas NVP exposure appeared to have an independent positive association.

Confidential image transfer: an ethico-legal dilemma

Clinical photographs aid decision-making and represent important medicolegal records. Storage and transfer of images of the facial area must adhere to Caldicott Principles. Outside working hours, clinical photography services are often limited. Our Trust has introduced a Secure Clinical Image Transfer (SCIT) app allowing clinicians to take photographs on personal devices to be securely uploaded to the patient's electronic health record. To evaluate whether clinicians were taking clinical images in an insecure manner, clinicians completed an anonymous questionnaire before and after introduction of the SCIT app. The standard was 100% knowledge of, and adherence to, trust information governance guidelines. Response rate was 100% in both cycles. Introduction of the SCIT app reduced inappropriate clinical photography on personal devices. Our completed audit cycle shows that the SCIT app allows convenient, secure information capture on personal devices and automatic secure synchronisation to trust electronic health records.

Geographic disparities in bladder cancer incidence among women in the department of Bouches-du-Rhône

Key messages

We identify for the first time a cluster of bladder cancers in women in France. Practitioners need to think about bladder cancers in women with urinary signs because this cancer will become a public health issue in the future.

Properties of Cosmic Helium Isotopes Measured by the Alpha Magnetic Spectrometer

Precision measurements by the Alpha Magnetic Spectrometer (AMS) on the International Space Station of ^{3}He and ^{4}He fluxes are presented. The measurements are based on 100 million ^{4}He nuclei in the rigidity range from 2.1 to 21 GV and 18 million ^{3}He from 1.9 to 15 GV collected from May 2011 to November 2017. We observed that the ^{3}He and ^{4}He fluxes exhibit nearly identical variations with time. The relative magnitude of the variations decreases with increasing rigidity. The rigidity dependence of the ^{3}He/^{4}He flux ratio is measured for the first time. Below 4 GV, the ^{3}He/^{4}He flux ratio was found to have a significant long-term time dependence. Above 4 GV, the ^{3}He/^{4}He flux ratio was found to be time independent, and its rigidity dependence is well described by a single power law ∝R^{Δ} with Δ=-0.294±0.004. Unexpectedly, this value is in agreement with the B/O and B/C spectral indices at high energies.

Crizotinib-induced immunogenic cell death in non-small cell lung cancer

Immunogenic cell death (ICD) converts dying cancer cells into a therapeutic vaccine and stimulates antitumor immune responses. Here we unravel the results of an unbiased screen identifying high-dose (10 µM) crizotinib as an ICD-inducing tyrosine kinase inhibitor that has exceptional antineoplastic activity when combined with non-ICD inducing chemotherapeutics like cisplatin. The combination of cisplatin and high-dose crizotinib induces ICD in non-small cell lung carcinoma (NSCLC) cells and effectively controls the growth of distinct (transplantable, carcinogen- or oncogene induced) orthotopic NSCLC models. These anticancer effects are linked to increased T lymphocyte infiltration and are abolished by T cell depletion or interferon-γ neutralization. Crizotinib plus cisplatin leads to an increase in the expression of PD-1 and PD-L1 in tumors, coupled to a strong sensitization of NSCLC to immunotherapy with PD-1 antibodies. Hence, a sequential combination treatment consisting in conventional chemotherapy together with crizotinib, followed by immune checkpoint blockade may be active against NSCLC.

Certain chemotherapeutic agents can exert their anticancer effect through indirect immune-dependent mechanism. Here, the authors screen a library of tyrosine kinase inhibitors and show that crizotinib is an effective stimulator of immunogenic cell death and can potentiate the efficacy of immune checkpoint blockade.

Towards Understanding the Origin of Cosmic-Ray Electrons

Precision results on cosmic-ray electrons are presented in the energy range from 0.5 GeV to 1.4 TeV based on 28.1×10^{6} electrons collected by the Alpha Magnetic Spectrometer on the International Space Station. In the entire energy range the electron and positron spectra have distinctly different magnitudes and energy dependences. The electron flux exhibits a significant excess starting from 42.1_{-5.2}^{+5.4}  GeV compared to the lower energy trends, but the nature of this excess is different from the positron flux excess above 25.2±1.8  GeV. Contrary to the positron flux, which has an exponential energy cutoff of 810_{-180}^{+310}  GeV, at the 5σ level the electron flux does not have an energy cutoff below 1.9 TeV. In the entire energy range the electron flux is well described by the sum of two power law components. The different behavior of the cosmic-ray electrons and positrons measured by the Alpha Magnetic Spectrometer is clear evidence that most high energy electrons originate from different sources than high energy positrons.

[Does diagnostic ureterorenoscopy increase the risk of bladder recurrence after total nephroureterectomy? A review of the literature]

OBJECTIVE

The objective of our study was to evaluate, in a review of the literature, the impact of diagnostic ureteroscopy before total nephroureterectomy (NUT) on the risk of bladder recurrence.

METHODS

We conducted a literature review in the Pubmed database in March 2018. Initial research identified 45 publications. Following full text screening, 9 studies were finally included, with a total of 1041 NUT with URS prior versus 2909 NUT alone. The primary endpoint was bladder recurrence. Secondary objectives were specific survival and overall survival.

RESULTS

Bladder recurrence was reported in the 9 studies included. Diagnostic ureteroscopy was significantly associated with an increased risk of post-NUT bladder recurrence (HZ 1.42 [1.29-1.56], P<0.01). The specific survival and overall survival at 5 years, were reported in respectively 4 and 2 studies. There was no impact of the pre-NUT diagnostic URS on the specific survival (HZ 0.75 [0.54-1.03], P=0.08) or post-NUT overall survival (HZ 1.15 [0.68-1.96], P=0.59).

CONCLUSION

The URS diagnostic before NUT for TVEUS is associated with a significant increase in the risk of postoperative bladder recurrence.

Giant Shot Noise from Majorana Zero Modes in Topological Trijunctions

The clear-cut experimental identification of Majorana bound states in transport measurements still poses experimental challenges. We here show that the zero-energy Majorana state formed at a junction of three topological superconductor wires is directly responsible for giant shot noise amplitudes, in particular at low voltages and for small contact transparency. The only intrinsic noise limitation comes from the current-induced dephasing rate due to multiple Andreev reflection processes.

Towards Understanding the Origin of Cosmic-Ray Positrons

Precision measurements of cosmic ray positrons are presented up to 1 TeV based on 1.9 million positrons collected by the Alpha Magnetic Spectrometer on the International Space Station. The positron flux exhibits complex energy dependence. Its distinctive properties are (a) a significant excess starting from 25.2±1.8  GeV compared to the lower-energy, power-law trend, (b) a sharp dropoff above 284_{-64}^{+91}  GeV, (c) in the entire energy range the positron flux is well described by the sum of a term associated with the positrons produced in the collision of cosmic rays, which dominates at low energies, and a new source term of positrons, which dominates at high energies, and (d) a finite energy cutoff of the source term of E_{s}=810_{-180}^{+310}  GeV is established with a significance of more than 4σ. These experimental data on cosmic ray positrons show that, at high energies, they predominantly originate either from dark matter annihilation or from other astrophysical sources.

Epitaxial growth of single-crystalline-film scintillators based on Tb3+-doped and Tb3+–Ce3+-codoped Gd1–xLuxAlO3 (x = 0–1) mixed perovskites

The paper is dedicated to the development of scintillating screens based on the single crystalline films of singly Tb³⁺ and doubly Tb³⁺–Ce³⁺ doped Gd_1–xLu_xAlO₃ (x = 0–1) perovskites grown onto YAlO₃ substrates using the liquid phase epitaxy method.