Radioactive Research Articles

Investigating the connection between γ-ray activity and the relativistic jet in 3C 273 during 2015−2019

Context. The powerful radiation over the entire electromagnetic spectrum and its radio jet activity of the blazar 3C 273 offer the opportunity of studying the physics of γ-ray emission from active galactic nuclei. Since the historically strong outburst in 2009, 3C 273 showed relatively weak emission in the γ-ray band over several years. However, recent Fermi-Large Area Telescope observations indicate higher activity during 2015−2019. Aims. We constrain the origin of the γ-ray outbursts toward 3C 273 and investigate their connection to the parsec-scale jet. Methods. We generated Fermi-LAT γ-ray light curves with multiple binning intervals and studied the spectral properties of the γ-ray emission. Using a 3 mm ALMA light curve, we studied the correlation between radio and γ-ray emission. The relevant activity in the parsec-scale jet of 3C 273 was investigated with 7 mm VLBA observations that were obtained close in time to notable γ-ray outbursts. Results. We find two prominent γ-ray outbursts in 2016 (MJD 57382) and 2017 (MJD 57883) accompanied by millimeter-wavelength flaring activity. The γ-ray photon index time series show a weak hump-like feature around the γ-ray outbursts. The monthly γ-ray flux–index plot indicates a transition from softer-when-brighter to harder-when-brighter states at 1.03 × 10−7 ph cm−2 s−1. A significant correlation between the γ-ray and millimeter-wavelength emission is found, and the radio lags the γ-rays by about 105−112 days. The 43 GHz jet images reveal the known stationary features (i.e., the core, S1, and S2) in a region upstream of the jet. We find an indication for a propagating disturbance and a polarized knot between the stationary components at about the times of the two γ-ray outbursts. Conclusions. Our results support a parsec-scale origin for the observed higher γ-ray activity, which suggests that this is associated with standing shocks in the jet.

ALMA 50-parsec-resolution Imaging of Jet–ISM Interaction in the Lensed Quasar MG J0414+0534

Abstract We report our high-resolution (0.″03–0.″07) Atacama Large Millimeter/submillimeter Array (ALMA) imaging of the quadruply lensed radio-loud quasar MG J0414+0534 at redshift z = 2.639 in the continuum and the broad CO(11−10) line at ∼340 GHz. With the help of strong lensing magnification and ALMA’s high resolution, we succeeded in resolving the jet/dust and CO gas in the quasar host galaxy, both extending up to ∼1 kpc, with a resolution of ∼50 pc for the first time. Both the continuum emission and the CO(11−10) line have a similar bimodal structure aligned with the quasar jets (∼200 pc) observed by Very Long Baseline Interferometry at 5 and 8.4 GHz. The CO gas in the vicinity of both the eastern and western jet components at the location of ∼80 pc from the quasar core are moving at high velocities, up to ±600 km s−1 relative to the core. The observed features show clear evidence of strong interaction between the jets and interstellar medium (ISM). High temperature and high-density environments in the ISM of the quasar host galaxy, as suggested from CO line ratios, also support this result. The small scale of the jets, the jet–ISM interaction, and the continuum spectral energy distribution of this source indicate that we are watching the infancy stage of quasar radio activity.

Comparison of 13N-NH3, 11C-MET and 18F-FDG PET/CT imaging in the diagnosis and evaluation of cerebral glioma

Objective To compare the application of 13N-NH3, 11C-methionine (MET) and 18F-fluorodeoxyglucose (FDG) PET/CT imaging in the diagnosis and evaluation of suspected cerebral glioma. Methods From September 2010 to December 2017, ninety patients (54 males, 36 females; age: (40.0±14.0) years) in the First Affiliated Hospital of Sun Yat-sen University with suspected glioma based on clinical diagnosis, who underwent 13N-NH3, 11C-MET and 18F-FDG PET/CT imaging, were prospectively enrolled in the study. All patients were confirmed by histology or clinical and radiological follow-up. Images were interpreted by visual evaluation (higher radioactive uptake in lesions than that in the contralateral normal brain parenchyma was considered as positive (+ ), equal/lower were considered as negative (-)) and semi-quantitative analysis (the maximum standardized uptake value (SUV) of lesion (L) to the mean SUV of normal white matter (WM) (L/WM ratio)). Receiver operating characteristic (ROC) curve analysis was used and the area under curves (AUCs) were calculated and compared. The diagnostic efficacies of 3 imaging methods and the combination for diagnosing gliomas and the abilities to differentiating high-grade gliomas (HGG) and low-grade gliomas (LGG) were compared. Results In 90 patients, 30 HGG, 27 LGG, 10 non-glioma brain tumors and 23 non-neoplastic lesions (NNL) were diagnosed. On visual evaluation, the sensitivities for differentiating tumors from NNL were 62.7%(42/67), 94.0%(63/67) and 35.8% (24/67) for 13N-NH3, 11C-MET and 18F-FDG PET/CT respectively, while the specificities were 95.7%(22/23), 56.5% (13/23) and 65.2% (15/23), and the accuracies were 71.1%(64/90), 84.4%(76/90) and 43.3% (39/90). Taking the metabolic patterns of + /+ /+ , + /+ /- and + /-/- (11C-MET/13N-NH3/18F-FDG) as the diagnosis standard of tumor lesions, the specificity and accuracy of the combined method increased to 73.9%(17/23) and 88.9%(80/90) with the sensitivity remaining the same (94.0%, 63/67). ROC curve analysis (L/WM) showed that the sensitivity, specificity and AUC were 64.2%(43/67), 100%(23/23) and 0.819 for 13N-NH3 PET/CT, and 89.6%(60/67), 69.6%(16/23) and 0.840 for 11C-MET PET/CT (z=-0.316, P>0.05). The accuracy for differentiating high and low grade glioma were 86.0% (49/57), 87.7%(50/57) and 93.0%(53/57) for 13N-NH3, 11C-MET and 18F-FDG PET/CT, with the AUC of 0.896, 0.928 and 0.964, respectively (z values: -0.554 to 1.334, all P>0.05). Conclusions 13N-NH3 PET/CT imaging has remarkably high specificity but low sensitivity for the differentiation of brain tumors from NNL. 11C-MET PET/CT imaging was found to be highly useful for detection of brain tumors. However, like 18F-FDG, high MET uptake is frequently observed in some NNL. 13N-NH3, 11C-MET and 18F-FDG PET/CT imaging all appear to be valuable for evaluating the histological grade of gliomas, and the combination of them is more useful for the accurate diagnosis of glioma. Key words: Glioma; Positron-emission tomography; Tomography, X-ray computed; NH3; Methionine; Deoxyglucose

Hard X-ray selected giant radio galaxies – II. Morphological evidence of restarted radio activity

ABSTRACT About 6 per cent of radio galaxies (RGs) can reach linear sizes larger than 0.7 Mpc, and are then classified as giant radio galaxies (GRGs). The conditions that make possible the formation of such big structures are still not clear – either core accretion properties or environmental factors. Recent studies have shown that GRGs can be up to four times more abundant in hard X-ray selected (i.e. from INTEGRAL/IBIS and Swift/BAT at >20 keV) RG samples. Moreover, a high fraction of young radio sources found in their cores suggest a recently restarted activity, as suggested from the discrepancy between the measured jet and lobes power, with respect to the one expected from core X-ray luminosity. Here, we present a radio morphological study of a sample of 15 hard X-ray selected GRGs, discussing low-frequency images from our GMRT campaign complemented with others from the literature: among them, 7/15 show evidence of restarted radio activity either in the form of double–double/X-shaped morphology, or as a cocoon emission embedding more recent jets. This, together with the objects from this sample already found hosting a young radio source in their core, suggests that at least 13 over 15 of these hard X-ray selected GRGs show features that are consistent with the possibility of restarted radio activity.

Comparison of 18F-Flurpiridaz and 13N-NH3·H2O PET/CT myocardial perfusion imaging in animal experiments

Objective To explore the biodistribution and quantitative value of 18F-Flurpiridaz in mini-swine, and compare with 13N-NH3·H2O. Methods Ten Bama mini-swine were divided into normal group and myocardial infarction group (n=5 in each group). Normal group was not treated and myocardial infarction group was modeled by thoracotomy and coronary artery ligation. Both groups were preceded by 13N-NH3·H2O imaging, followed by 18F-Flurpiridaz imaging (time interval >40 min). Injection dosage of 2 tracers was the same (185-370 MBq). 18F-Flurpiridaz whole-body PET/CT imaging was also performed in normal group. Biological distribution of 18F-Flurpiridaz was observed, and the ratio of radioactive uptake of 18F-Flurpiridaz between myocardium and adjacent tissues or organs was calculated. Image quality score and rest myocardial blood flow (rMBF) of 2 imaging tracers in normal group were measured and compared. MPI image quality score, cardiac function parameters such as summed rest score (SRS), myocardial infarction area percentage, total perfusion defect (TPD), and left ventricular ejection fraction (LVEF) of 2 imaging tracers were compared in myocardial infarction group. Data was analyzed by paired t test. Results In normal group, 18F-Flurpiridaz in the myocardium was clearly observed, with high radioactive uptake maintaining within 2 h postinjection. The radioactivity count ratios of left ventricular myocardium to cardiac pool, the lungs and liver were high (5.19-12.87, 4.17-50.51, 2.08-6.92). The quality of 18F-Flurpiridaz MPI images in both groups was excellent (10/10). The rMBF (ml·g-1·min-1) in different regions of left ventricle measured by 18F-Flurpiridaz and 13N-NH3·H2O imaging were not significantly different (left anterior descending: 0.98±0.06 vs 0.92±0.13; left circumflex: 0.98±0.05 vs 0.88±0.12; right coronary artery: 0.95±0.07 vs 0.88±0.15; left ventricle: 0.96±0.07 vs 0.90±0.13; t values: from -1.70 to -0.90, all P>0.05). There was no significant difference in SRS, myocardial infarction area percentage, TPD, rMBF or LVEF between 18F-Flurpiridaz and 13N-NH3·H2O (SRS: 10.6±4.1 vs 9.2±4.6; myocardial infarction area percentage: (15.2±9.0)% vs (12.6±6.6)%; TPD: (11.6±6.3)% vs (9.6±3.9)%; LVEF: (68.6±11.1)% vs (71.4±11.3)%; t values: -2.33-2.75, all P>0.05). Conclusions Comparing with 13N-NH3·H2O, 18F-Flurpiridaz has the advantages of good MPI image quality, accurate measurement of cardiac function parameters and quantitative potential of myocardial blood flow, which make it as a promising positron myocardial perfusion imaging agent. Key words: Myocardial perfusion imaging; Pyridazines; Fluorine radioisotopes; Ammonia; Positron-emission tomography; Tomography, X-ray computed; Swine

Research progress of pretargeting strategies in antibody radiolabeling

Pretargeting is an imaging strategy different from the imaging of traditional radiolabeled antibody, in which the antibody and radioisotope are administered in turn and then combined by coupling system within the body. Due to the high specificity and affinity between the coupling systems, the radioisotope is localized to the target in vivo, and then the radioactive labeling is achieved for imaging. Nuclear imaging using pretargeting methods can decrease the circulation duration of the radioisotope so as to reduce the uptake of the radioactivity in normal tissues, and facilitate the use of short-lived radioisotopes. This article provides a bird′s-eye view of 4 main strategies: biotin-streptavidin (SA) system, bispecific antibodies (BsAb) system, complementary oligonucleotides sequence, and bioorthogonal click chemistry system. Key words: Radioimmunodetection; Isotope labeling; Antibodies; Trends

Experimental study of SPECT imaging with novel myocardial perfusion imaging tracer: 99Tcm-3SPboroxime

Objective To assess the superiority of 99Tcm-3SPboroxime (99Tcm-3SP for short) as a fast-myocardial perfusion imaging (MPI) tracer in normal and acute myocardial infarction (AMI) mini-swine. Methods 99Tcm-3SP and 99Tcm-Teboroxime (99Tcm-TEBO for short) were prepared. Approximately 370 MBq 99Tcm-3SP or 99Tcm-TEBO was injected intravenously in 2 healthy mini-swine separately. Dynamic planar images were acquired immediately after injection and continued for 20 min using a standard SPECT camera. The radioactivity uptakes in the heart, liver, and lungs were measured, and heart/liver and heart/lung ratios over time were calculated. Dynamic SPECT studies were performed in 4 normal swine and 1 AMI-swine using cadmium zinc telluride-SPECT (CZT-SPECT). List mode acquisitions were immediately started and continued for 15 min after intravenous injection of approximately 370 MBq 99Tcm-TEBO and 99Tcm-3SP. The injection of two radiotracers in the same swine was completed within 2 d. The radioactivity uptakes in heart and liver were measured, and heart/liver ratio was calculated. Image quality was also evaluated. Paired t test was used to analyze the data. Results The radiochemical purity of 99Tcm-TEBO or 99Tcm-3SP were both above 95%. The initial heart uptake of 99Tcm-3SP was very close to that of 99Tcm-TEBO (planar image, 2 min postinjection: 309.32×103vs 314.13×103 counts/MBq; SPECT image, 2 min postinjection (corrected): 7.96±0.87 vs 8.24±1.53, t=0.277, P>0.05), but the myocardial retention time was much longer than that of 99Tcm-TEBO (planar image, 20 min postinjection: 218.67×103vs 143.19×103 counts/MBq; SPECT image, 15 min postinjection (corrected): 6.76±0.45 vs 5.06±0.33, t=-12.412, P=0.001). The uptake of liver and heart/liver ratio between 99Tcm-TEBO and 99Tcm-3SP were similar (t values: -1.332-1.101, all P>0.05 within 15 min). SPECT MPI images demonstrated uniform tracer distribution with clearly visualizable myocardial boundary in normal myocardium and intense perfusion defect in infarct myocardium. High quality SPECT images could be obtained in any of the 5 min imaging windows over the first 15 min after injection of 99Tcm-3SP in normal swine and AMI-swine. Conclusion 99Tcm-3SP is a promising 99Tcm-labeled radiotracer for fast-MPI considering its high heart uptake, long myocardial retention time (20 min postinjection) and superior SPECT image quality. Key words: Myocardial perfusion imaging; Oximes; Boronic acids; Technetium; Tomography, emission-computed, single-photon; Swine

Evaluation of left ventricular systolic function and synchrony in patiests with early left breast cancer after breast conserving radiotherapy by layer-specific strain technique

Objective To evaluate the left ventricular systolic function and synchronization of patients with early left breast cancer after breast conserving radiotherapy by layer-specific strain technique. Methods Thirty-six patients with early left breast cancer who underwent breast surgery and radiotheraphy in Affiliated Tumor Hospital of Zhengzhou University from January 2018 to January 2019 were selected for this study. The layered strain technique was respectively applied to collect two-dimensional dynamic ultrasonic cardiograms one week before radiotherapy, one week after radiotherapy, and six months after radiotherapy. The EchoPAC 201 software was applied to analyze and obtain the global longitudinal peak strain(GLPS) and peak stain dispersion(PSD) of the epicardial layer(epi), the middle layer(mid) and endocardial layer(endo) of 17 left ventricular segments. The differences of every parameter before and after radiotherapy were compared, and the correlation of PSD and other parameters was analyzed. Results Compared with one week before radiotherapy, the absolute values of LPSepi, LPSmid, LPSendo, and GLPS all reduced significantly one week and six months after radiotherapy, and PSD increased significantly (P<0.05). Compared with one week after radiotherapy, the LPS absolute value of every layer and GLPS obviously reduced after six months, PSD obviously increased, the difference had statistical significance (P<0.05). PSD and GLPS displayed negative correlation one week after radiotherapy (r=-0.420, P<0.05), PSD and GLPS displayed negative correlation six months after radiotherapy (r=-0.641, P<0.05). Conclusions Layered strain technique can noninvasively and quantitatively evaluate the early changes of global and layered longitudinal peak strain and systolic synchrony of left ventricle in left breast cancer breast-conserving radiotherapy patients, and provides a new noninvasive test method for evaluating radioactive myocardial injury, and it has a certain guiding value to early clinical intervention and treatment of cardiovascular complications. Key words: Breast cancer, early; Radiotherapy; Layer-specific strain; Peak strain dispersion

The X-ray and radio activity of typical and luminous Ly α emitters from z ∼ 2 to z ∼ 6: evidence for a diverse, evolving population

ABSTRACT Despite recent progress in understanding Ly α emitters (LAEs), relatively little is known regarding their typical black hole activity across cosmic time. Here, we study the X-ray and radio properties of ∼4000 LAEs at 2.2 &amp;lt; $z$ &amp;lt; 6 from the SC4K survey in the COSMOS field. We detect 254 ($6.8{\rm{ per\ cent}} \pm 0.4{\rm{ per\ cent}}$) LAEs individually in the X-rays (S/N &amp;gt; 3) with an average luminosity of $\rm 10^{44.31\pm 0.01}\, erg\, s^{-1}$ and average black hole accretion rate (BHAR) of $\rm 0.72 \pm 0.01$ M⊙ yr−1, consistent with moderate to high accreting active galactic neuclei (AGNs). We detect 120 sources in deep radio data (radio AGN fraction of $3.2{\rm{ per\ cent}} \pm 0.3{\rm{ per\ cent}}$). The global AGN fraction ($\rm 8.6{\rm{ per\ cent}} \pm 0.4{\rm{ per\ cent}}$) rises with Ly α luminosity and declines with increasing redshift. For X-ray-detected LAEs, Ly α luminosities correlate with the BHARs, suggesting that Ly α luminosity becomes a BHAR indicator. Most LAEs ($93.1{\rm{ per\ cent}} \pm 0.6{\rm{ per\ cent}}$) at 2 &amp;lt; $z$ &amp;lt; 6 have no detectable X-ray emission (BHARs &amp;lt; 0.017 M⊙ yr−1). The median star formation rate (SFR) of star-forming LAEs from Ly α and radio luminosities is $7.6^{+6.6}_{-2.8}$ M⊙ yr−1. The black hole to galaxy growth ratio (BHAR/SFR) for LAEs is &amp;lt;0.0022, consistent with typical star-forming galaxies and the local BHAR/SFR relation. We conclude that LAEs at 2 &amp;lt; $z$ &amp;lt; 6 include two different populations: an AGN population, where Ly α luminosity traces BHAR, and another with low SFRs which remain undetected in even the deepest X-ray stacks but is detected in the radio stacks.

Brachytherapy for Intermediate-Risk Prostate Cancer

Brachytherapy is the implantation of radioactive material into a tumor. No randomized trials have been performed to compare radical prostatectomy,

Oxycodone hydrochloride sustained release tablets combined with radioactive 125iodine seed implantation in the treatment of lung cancer pain: one case report

Oxycodone hydrochloride sustained release tablets combined with radioactive 125iodine seed implantation in the treatment of lung cancer pain: one case report

Editor’s Foreword

The 2019 edition of the IEEE Radio and Antenna Days of the Indian Ocean (IEEE RADIO 2019) international conference was hosted in Reunion Island for the second time. This seventh edition of the conference was held from 23rd to 26th September 2019 at the Lux Resort & Hotel, Saint-Gilles Les Bain. The conference was managed by the Radio Society (Mauritius) and financially sponsored by the IEEE Antennas and Propagation Society (AP-S). Région Réunion financially supported the conference and Union Radio Scientifique Internationale (URSI). provided technical co-sponsorship. The Local Organising Committee consisted of researchers from CentraleSupélec, France, University of Mauritius and University of Reunion Island.IEEE RADIO 2019 was attended by participants from about twenty different countries. The conference featured a tutorial on the design of radio amateur networks followed by presentations of radio amateur activities in Mauritius and Reunion Island. Projects related to humanitarian activities were discussed during a special session organized by the IEEE Special Interest Group on Humanitarian Technology (SIGHT) Indian Ocean. Two workshops, open to all the participants of the conference, were organized in conjunction with the conference. The first workshop addressed measurements and simulations for industrial applications and development of standards. The second workshop was dedicated to the CARERC (Cartographie Electromagnétique par Réseaux de Capteurs) project that was undertaken by colleagues at University of Reunion Island during the past years. The regular sessions covered topics such antenna design, bioelectromagnetics, devices and circuits, wireless communication and tracking systems. Three internationally recognized scientists delivered invited talks during the conference.The oral presentations of students and young scientists were evaluated by a jury. A shield and a cash prize of 300 Euros were awarded to the Best Young Scientist less than 36 years old. The presenters of the first, second and third Best Student Papers were awarded shields and cash prizes of 300 Euros, 200 Euros and 100 Euros, respectively. The AP-S sponsored Industrial Engineering Paper Award, consisting of a shield and a cash prize of 300 Euros, was presented to the author of the paper presenting the most innovative and significant contribution in terms of practical industrial engineering related to the fields of antennas, electromagnetics and propagation.All the 2-page short papers that were effectively presented during the conference have already been published on the IEEE Xplore Digital Library. A call for the submission of 4-page extended versions of the conference papers was launched for publication as a volume in the IoP Conference Series: Materials and Engineering (MSE). After the peer-review process by the distinguished members of the Scientific Committee, only four papers were accepted and published in this volume of IoP Conference Series: MSE.EditorVikass Monebhurrun

Value of pathogenic diagnosis of 18F-FDG PET/CT imaging in non-traumatic unilateral vocal cord paralysis

Objective To evaluate the diagnostic value of 18F-fluorodeoxyglucose (FDG) PET/CT imaging in non-traumatic unilateral vocal cord paralysis (UVCP) and compare the radioactive uptake in different lesions. Methods Clinical data of 62 patients (49 males, 13 females; age: (61.7±12.8) years) with non-traumatic UVCP (43 cases of left vocal cord paralysis and 19 cases of right) admitted to Ji′an Hospital from January 2016 to December 2018 were analyzed retrospectively. Pathological results, imaging or follow-up results were considered as the standard of final diagnosis. The diagnostic efficacy of PET/CT imaging for the primary cause was analyzed. The maximum standardized uptake values (SUVmax) of vocal cord in patients with different etiology were compared by independent-sample t test. Results According to the final diagnosis, the primary causes of UVCP were as follows: malignant tumors (n=44), inflammation (n=16), glomus jugulare tumor (n=1) and idiopathic UVCP (n=1). The diagnostic accuracy of PET/CT imaging for the primary cause was 90.32%(56/62): 44 cases were correctly diagnosed as malignant tumors, while 11 cases as inflammation, and 1 case as glomus jugulare tumor. Among 62 patients, 29 patients had increased SUVmax in the affected side (direct invasion group; further divided into tumor group (n=12) and non-tumor group (n=17)), and other 33 patients had increased SUVmax in the healthy side (indirect invasion group). SUVmax of the affected vocal cord in direct invasion group was higher than that in the healthy side (9.97±5.21 vs 2.43±0.62; t=8.14, P 0.05). Conclusions 18F-FDG PET/CT imaging has high diagnostic value in pathogenic diagnosis of non-traumatic UVCP. The different radioactive uptake of vocal cords in the affected side and the healthy side provides more accurate etiological information for clinical analysis. Key words: Vocal cord paralysis; Positron-emission tomography; Tomography, X-ray computed; Deoxyglucose

The Creative Economy in the State of Amazonas/Brazil: Analysis From Data Available in the Ministry of Labor and Social Security Between 2006 and 2015

This research aims to analyze the creative economy in the state of Amazonas/Brazil between 2006 and 2015 from the Annual Report of Social Information (RAIS). The research is characterized as quantitative and descriptive. Regarding the design, there is documentary research. The delimitation of the universe considered the establishments and bonds considered creative from 44 economic activities of the creative economy. The main results include: growth in the number of creative establishments between 2006 and 2015; growth in the number of creative bonds in the same period; radio, culture, and art activities and open television activities are mostly inland; while in the capital, activities related to information technology services, language teaching and advertising agencies; maintenance of the creative economy's share in the state's overall total although growth was observed in absolute terms; and almost all creative establishments are micro and small businesses. The relevance of the work lies in the regionalization of this type of research in order to base future discussions regarding public policies specific to the creative economy in the state.

Radioactive Biliary Stents for Unresectable Malignant Obstructive Jaundice

Radioactive or radiolabeled biliary stents have been discussed for many years, but none have come to market in the U.S. These stents could potentially

Radiological hazards due to natural radioactivity and radon concentrations in water samples at Al-Hurrah city, Iraq

Radiological hazards due to natural radioactivity and radon concentrations in water samples at Al-Hurrah city, Iraq

The Massive and Distant Clusters of WISE Survey. VII. The Environments and Properties of Radio Galaxies in Clusters at z ∼ 1

Abstract We present the results from a study with NSF’s Karl G. Jansky Very Large Array (VLA) to determine the radio morphologies of extended radio sources and the properties of their host galaxies in 50 massive galaxy clusters at z ∼ 1. We find a majority of the radio morphologies to be Fanaroff–Riley type IIs. By analyzing the infrared counterparts of the radio sources, we find that ∼40% of the host galaxies are the candidate brightest cluster galaxy and ∼83% are consistent with being one of the top six most massive galaxies in the cluster. We investigate the role of environmental factors on the radio-loud AGN population by examining correlations between environmental and radio-galaxy properties. We find that the highest stellar mass hosts (M * ≳ 4 × 1011 M ⊙) are confined to the cluster center and host compact jets. There is evidence for an increase in the size of the jets with cluster-centric radius, which may be attributed to the decreased ICM pressure confinement with increasing radius. Besides this correlation, there are no other significant correlations between the properties of the radio-AGN (luminosity, morphology, or size) and environmental properties (cluster richness and location within the cluster). The fact that there are more AGN in the cluster environment than the field at this epoch, combined with the lack of strong correlation between galaxy and environmental properties, argues that the cluster environment fosters radio activity but does not solely drive the evolution of these sources at this redshift.

Differences in radio emission from similar M dwarfs in the binary system Ross 867-8

Serendipitously, we rediscovered radio emission from the binary system Ross 867 (M4.5V) and Ross 868 (M3.5V) while inspecting archival Giant Metrewave Radio Telescope (GMRT) observations. The binary system consists of two M-dwarf stars that share common characteristics such as spectral type, astrometric parameters, age, and emission at infrared, optical, and X-ray frequencies. The GMRT data at 610 MHz taken on July 2011 shows that the radio emission from Ross 867 is polarized and highly variable on hour timescales with a peak flux of 10.4 ± 0.7 mJy beam−1. Additionally, after reviewing archival data from several observatories (VLA, GMRT, JVLA, and LOFAR), we confirm that although the two stars are likely coeval, only Ross 867 was detected, while Ross 868 remains undetected at radio wavelengths. As the stars have a large orbital separation, this binary stellar system provides a coeval laboratory to examine and constrain the stellar properties linked to radio activity in M dwarfs. We speculate that the observed difference in radio activity between the dwarfs could be due to vastly different magnetic field topologies or that Ross 867 has an intrinsically different dynamo.

Grape extract protect against ionizing radiation-induced DNA damage

Grape extracts of different cultivars (Flame seedless, Kishmish chorni, Red globe and Thompson seedless) were investigated for in vitro antioxidant activity by ABTS assay, and compared protective efficacy against radiation-induced DNA damage. Seed extract showed the highest scavenging activity, followed by skin extract. Among different cultivars, ‘flame seedless’ skin extract showed higher scavenging activity followed by ‘Kishmish chorni’ skin extract. Grape extracts significantly prevented radiation-induced plasmid DNA damage. Super-coiled pBR 322 plasmid DNA (~93%) is completely converted to open circular (~97%) and linear (~2%) form at a dose of 150 Gy γ-radiation. Pretreatment with different grape extracts showed various degree of protection against radiation-induced DNA damage. Pretreatment with 1.6 µg grape skin extract of ‘Thompson seedless’ cultivar or grape flesh extract of any tested cultivar diminished the DNA strand breaks, and there was an increase in the super coiled form of DNA against 150 Gy of γ-radiation. However, pretreated pBR 322 DNA with the skin of ‘Kishmish chorni’ cultivars or seed of ‘red globe’ grape cultivars remained static during electrophoresis and confined in the groove on exposure to 150 Gy γ-radiation treatment. Co-treatment with the skin of red globe cultivar also partially confined plasmid DNA in the groove. The same trend was observed when plasmid DNA was exposed to 1.2 kGy γ-radiation. Our investigation revealed that anthocyanin present in grape skin was probably involved in radio protective activities through the formation of co-pigmentation with DNA.

Investigation on 90Sr concentrations in foods near Ningde Nuclear Power Plant in 2013-2017

Objective To investigate the 90Sr concentration levels in the monitoring areas and the control area at Ningde Nuclear Power Plant (NPP). Methods Food samples were collected from the monitoring areas in 30 km of Ningde NPP and the control area far away. The radioactive levels of 90Sr in food samples were analyzed using the chromatography with 2-(2-ethylhexyl) phosphate fast extraction method. Results In this survey, 90Sr radioactive concentrations in 30 varieties of foods in 6 categories were analyzed. In the monitoring area, 90Sr radioactivity concentration in the samples collected were in the range of 0.017-1.830 Bq/kg for cereals, beans and potatoes, 0.021-0.318 Bq/kg for vegetables, 0.007-7.690 Bq/kg for quatic products, and 0.009-0.184 Bq/kg for meats; whereas, in the control area, cereals, beans and potatoes in 0.017-0.700 Bq/kg, vegetables in 0.034-0.677 Bq/kg, aquatic products in 0.038-3.360 Bq/kg, and meats in 0.019-0.054 Bq/kg. Conclusions The 90Sr radioactive concentrations in foods were far below the food standard limits in this survey. The contribution of evaluated to the public from the 90Sr in foods was neglectable. Key words: Nuclear power plant; Food; Radioactive levels; 90Sr