Fantastic Fits with fantasy of Active Galactic Nuclei Spectra -- Exploring the Fe II emission near the Hα\alpha line

In this study, a refined approach for multicomponent fitting of active galactic nuclei (AGN) spectra is presented utilizing the newly developed Python code $fantasy$ (fully automated python tool for AGN spectra analysis). AGN spectra are modeled by simultaneously considering the underlying broken power-law continuum, predefined emission line lists, and an Fe II model, which is here extended to cover the wavelength range 3700 - 11000 A. The Fe II model, founded solely on atomic data, effectively describes the extensive emission of the complex iron ion in the vicinity of the H$\gamma$ and H$\beta$ lines, as well as near the H$\alpha$ line, which was previously rarely studied. The proposed spectral fitting approach is tested on a sample of high-quality AGN spectra from the Sloan Digital Sky Survey (SDSS) Data Release 17. The results indicate that when Fe II emission is present near H$\beta$, it is also detected redward from H$\alpha$, potentially contaminating the broad H$\alpha$ line wings and thus affecting the measurements of its flux and width. The production of Fe II emission is found to be strongly correlated with Eddington luminosity and appears to be controlled by the similar mechanism as the hydrogen Balmer lines. The study highlights the benefits of fitting AGN type 1 spectra with the $fantasy$ code, pointing that it may be used as a robust tool for analyzing a large number of AGN spectra in the coming spectral surveys.Comment: Accepted in ApJ

The intrinsic Baldwin effect in broad Balmer lines of six long-term monitored AGNs

We investigate the intrinsic Baldwin effect (Beff) of the broad H$\alpha$ and H$\beta$ emission lines for six Type 1 active galactic nuclei (AGNs) with different broad line characteristics: two Seyfert 1 (NGC 4151 and NGC 5548), two AGNs with double-peaked broad line profiles (3C 390.3 and Arp 102B), one narrow line Seyfert 1 (Ark 564), and one high-luminosity quasar with highly red asymmetric broad line profiles (E1821+643). We found that a significant intrinsic Beff was present in all Type 1 AGNs in our sample. Moreover, we do not see strong difference in intrinsic Beff slopes in different types of AGNs which probably have different physical properties, such as inclination, broad line region geometry, or accretion rate. Additionally, we found that the intrinsic Beff was not connected with the global one, which, instead, could not be detected in the broad H$\alpha$ or H$\beta$ emission lines. In the case of NGC 4151, the detected variation of the Beff slope could be due to the change in the site of line formation in the BLR. Finally, the intrinsic Beff might be caused by the additional optical continuum component that is not part of the ionization continuum.Comment: 12 pages, 8 figures, Accepted for publication in A&

Značaj i upotreba žita u ishrani riba

Proizvodnja hrane za ribe, poslednjih godina beleži najbrži rast u industrijskoj proizvodnji hrane za životinje (Jovanović i sar. 2006). Ukoliko sektor akvakulture nastavi sa dosadašnjim prosečnim rastom od 8-10% godišnje do 2025. godine, i proizvodnja hrane moraće da prati taj rast (Tacon,2010). Danas se u hranu za ribe uglavnom uključuju riblje brašno i riblje ulje zbog visoke nutritivne vrednosti. Zbog ograničenosti prirodnih resursa. nameće se potreba za značajnijim uključivanjem biljnih hraniva, pre svega žita u ishrani riba. Žita prvenstveno predstavljaju izvor energije i služe za prihranu riba, međutim, njihovom preradom mogu se dobiti koncentati proteina koji se mogu koristiti kao delimična zamena za proteine animalnog porekla. Žita kao energetska hraniva čine osnovni deo obroka u poluintenzivnom sistemu gajenja riba. Proteinski deo potreba obezbeđuje im fauna dna i zooplankton. U našoj zemlji kukuruz je najvažnije žito koja se koristi u ishrani životinja. Visok sadržaj skroba, srazmerno velika zastupljenost ulja i malo celuloze, čini kukuruz izrazito energetskim hranivom (Đorđević i Dinić, 2007). Kukuruz karakteriše nizak sadržaj proteina sa nepovoljnim aminokiselinskim sastavom. Protein kukuruza pretežno čini zein koji ima nisku nutritivnu vrednost, pre svega usled deficita lizina i triptofana. Proteini ječma su niske biološke vrednosti, ali nešto bolji u odnosu na proteine kukuruza (Perović, Janković et al.,2009). Siromašni su u lizinu i metioninu, mada su selekcijom dobijene sorte sa većim sadržajem lizina. U poređenju sa kukuruzom, po hranljivoj vrednosti, pšenica sadrži više proteina, a manje masti. Sadržaj proteina kod različitih sorata pšenice varira od 10-14% (Protić, Janković,1998). Proteini pšenice su siromašni lizinom, zatim metioninom, treoninom, leucinom i izoleucinom (Janković et al.,2008). Količina lizina, koji je prva limitirajuća aminokiselina, iznosi 0,3-0,37%. Tritikale je hibrid pšenice i raži, koji se zbog relativno visoke nutritivne vrednosti sve više se koristi u ishrani svih kategorija životinja, pa i riba. Tritikale sadrži 11-20% sirovih proteina. Sadržaj aminokiselina je sličan sadržaju aminokiselina pšenice. Najsavremeniju tehnološku operaciju u procesu proizvodnje hrane za ribe predstavlja proces ekstrudiranja. Ekstruzionim kuvanjem na principu «visoka temperatura-kratko vreme» postižu se veca svarljivosti skroba, veća nutritivna vrednost, plutanje ili sporo tonjenje sto omogucava vece učesće žita u hrani za ribe. (Jovanović et al.2006).. Žita kao komponente u kompletnim smešama za ribe u intenzivnom uzgoju imaju izuzetno veliki značaj, posebno u ishrani šarana koji značajan deo energetskih potreba može zadovoljiti iz skroba. Proteinska hraniva, uz dodatak sintetičkih aminokiselina dobijena preradom žita, poput kukuruznog, pšeničnog glutena, kao i proteina pirinča, u značajnoj meri mogu zameniti, riblje brašno kao najkvalitetnije hranivo u ishrani riba. Selekcijom i genetskim modofikacijama treba stvarati žita sa povoljnim nutritivnim svojstvima potrebnim za hranu za ribe

Natural radioactivity in imported ceramic tiles used in Serbia

Ceramic tiles are one of the commonly used decorative building materials. Body of ceramic tiles is a mixture of different raw materials including clays, quartz materials and feldspat, and may be glazed or left unglazed. Due to the presence of zircon in the glaze, ceramic tiles can show natural radioactivity concentration significantly higher than the average values for building materials. This study presents a summary of results obtained by a survey which was consisted of measurements of activity concentrations of natural radionuclides in imported ceramic tile samples used in Serbia using a gamma spectrometer with HPGe detector. Based on the obtained concentrations, gamma index, radium equivalent activity, the indoor absorbed dose rate and the corresponding annual effective dose were evaluated to assess the potential radiological hazard associated with these building materials

Regulation of expression of the cell adhesion molecule Echinoid and its effect on the actin cytoskeleton during Drosophila melanogaster development

Echinoid (Ed) is a homophilic cell adhesion molecule previously implicated in the regulation of the actin cytoskeleton during the development of Drosophila melanogaster. In the ovary, borders between populations of follicle cells that express Ed and those that lack Ed are associated with localized contractile actomyosin structures that function in the normal morphogenesis of this epithelium. Such contractile actomyosin structures also assemble at the borders of ed mutant follicle cell clones, which develop smooth interfaces with surrounding Ed-expressing cells. In the embryo, a differential Ed-expression border between the embryonic epidermis and the amnioserosa is likewise associated with a contractile actomyosin cable.Since Ed protein becomes asymmetrically localized in Ed-expressing cells that are adjacent to cells without Ed, a model for Ed function has been proposed in which the planar polarized distribution of Ed induces actomyosin cable assembly at interfaces of differential Ed expression. However, such localized actomyosin cable formation could also be explained by an alternative model in which Ed acts as a negative regulator of actomyosin assembly at interfaces where it is localized. Here, I investigate these two alternative models for Ed function in the regulation of the actin cytoskeleton by analyzing ed mutant clones in the ovary. By analyzing the effect of ed mutant clone size on apical area of ed mutant cells I provide evidence that apical area of ed mutant cells is affected by actomyosin contractility generated at clone borders, consistent with the hypothesis that actomyosin assembly is induced by the asymmetric distribution of Ed in cells surrounding ed clones. I also present data that suggest that the actomyosin component F-actin is enriched at the borders of ed mutant clones relative to interfaces between ed mutant cells or between Ed-expressing cells, consistent with the hypothesis that asymmetric distribution of Ed induces actomyosin cable assembly at this site. However, my analysis also reveals that F-actin accumulates at interfaces between ed mutant cells at higher than levels at interfaces between Ed-expressing cells. Therefore, this finding suggests a potential role for Ed in the negative regulation of actomyosin.Since the upstream factors that establish the differential expression of Ed between the embryonic epidermis and amnioserosa during dorsal closure are unknown, I also investigated the transcription factor Grainyhead (Grh) as a candidate regulator of Ed expression in the embryo. I found that although ectopic expression of Grh is sufficient to induce the ectopic expression of Ed in the amnioserosa, grh function is not required for the normal expression of Ed in the embryonic epidermis or in the ovary. These findings suggest that other factors are responsible for the regulation of Ed in the ovary and the embryo, and for the establishment of differential Ed expression interfaces in these tissues.Echinoid (Ed), une molécule d'adhésion homophilique, a précédemment été impliquée dans la régulation du cytosquelette d'actine durant le développement chez la drosophile (Drosophila melanogaster). Dans l'ovaire, des structures contractiles d'actomyosine sont associées à la frontière entre les cellules folliculaires exprimant Ed et celles n'exprimant pas Ed. Ces structures ont une fonction au cours de la morphogénèse de l'épithélium folliculaire ovarien normal. Une telle structure contractile d'actomyosine est aussi visible à la limite entre les clones de cellules folliculaires mutantes pour ed et les cellules folliculaires normales de l'épithélium, créant ainsi une délimitation lisse entre les deux populations de cellules. Dans l'embryon, une expression différentielle endogène d'Echinoid est aussi retrouvée entre les cellules épidermiques et les cellules de l'amniosérose, menant à l'assemblage d'un câble contractile d'actomyosine. Dans les cellules exprimant Ed adjacentes à celles n'exprimant pas Ed, la protéine Ed sera asymétriquement localisée, d'où le modèle proposé pour la fonction d'Echinoid où la distribution polarisée plane d'Ed induit l'assemblage d'un câble d'actomyosine à l'interface d'une expression différentielle d'Ed. Toutefois, le modèle alternatif propose que la protéine Echinoid agisse comme un régulateur négatif sur l'assemblage d'un câble d'actomyosine aux interfaces où elle est localisée. Le projet présenté ici étudie ces deux modèles alternatifs par l'analyse des clones de cellules mutantes pour ed dans l'ovaire. L'analyse de l'effet de la taille des clones de cellules mutantes pour ed sur l'aire apicale de ces cellules mutantes démontre que cette aire apicale est affectée par la contraction du câble d'actomyosine généré à la frontière du clone de cellules mutantes. Ceci est cohérent avec l'hypothèse voulant que l'assemblage du câble d'actomyosine soit induit par une distribution asymétrique d'Ed dans les cellules entourant un clone de cellules mutantes pour ed. De plus, les données révèlent que l'actine F, un composant du câble d'actomyosine, est enrichi à la frontière entre les cellules mutantes pour ed et les cellules de type normal exprimant Ed par rapport aux différents interfaces entre ces cellules elles-mêmes. Ceci appuie l'hypothèse que la distribution asymétrique d'Ed induit l'assemblage d'un câble d'actomyosine à cet endroit. Toutefois, l'analyse révèle également que l'actine F s'accumule aux interfaces entre les cellules mutantes pour ed à des niveaux plus élevés qu'aux interfaces entre les cellules exprimant Ed. Ce résultat suggère un rôle probable pour Ed dans la régulation négative du câble d'actomyosine.Les facteurs impliqués en amont pour établir une expression différentielle d'Ed entre les cellules épidermiques et les cellules de l'amniosérose durant l'étape de fermeture dorsale de l'embryon sont encore inconnus. Le facteur de transcription Grainyhead (Grh) a ainsi été évalué comme candidat à la régulation de l'expression d'Ed dans l'embryon. Bien qu'une expression ectopique de Grh est suffisante pour induire l'expression d'Ed dans les cellules de l'amniosérose, la fonction de Grh n'est pas requise pour l'expression normale d'Ed dans les cellules épidermiques embryonnaires ou dans l'ovaire. Ces résultats suggèrent que d'autres facteurs soient responsables de la régulation d'Echinoid dans l'ovaire et dans l'embryon ainsi que pour l'établissement d'une expression différentielle d'Ed dans ces tissus

Psychosocial school factors and mental health of first grade secondary school students-Results of the Health Behaviour in School-aged Children Survey in Serbia.

This cross-sectional study aimed to investigate the association between psychosocial school factors and life satisfaction, symptoms of depression and psychosomatic health complaints among first grade secondary school students in Serbia. We analysed data from the 2018 Health Behaviour in School-aged Children (HBSC) study in the Republic of Serbia. Analyzed psychosocial school factors included satisfaction with school, schoolwork pressure, teacher support, classmate support and being bullied at school. Life satisfaction was assessed by the 11-step Cantril's ladder (cutoff >5). Symptoms of depression were measured by the Center for Epidemiologic Studies Depression Scale (CESD-10) and psychosomatic health complaints by using the HBSC symptom checklist. Univariable and multivariable binary logistic regression was used to determine independent predictors of students' life satisfaction, symptoms of depression and psychosomatic health complaints in the school environment, while also considering their socio-demographic characteristics and perceived family and friend support. The study included 1605 students (average age 15.26 ±0.44 years), of whom 50.3% were females. Results from the binary logistic regression analyses showed that life satisfaction was positively related to school satisfaction and classmate support, and negatively to being bullied at school. Symptoms of depression were positively associated with schoolwork pressure and being bullied at school, and negatively with teacher and classmate support. All analyzed factors of the school environment were significantly related to psychosomatic health complaints, whereby schoolwork pressure and being bullied at school were positively associated, while teacher and classmate support and satisfaction with school were negatively associated. Given the established association of psychosocial school factors with mental health, there is a need for targeted measures both at school and community level with the aim of improving social support in the school environment, reducing schoolwork burden and preventing bullying at school, potentially resulting in the overall improvement of mental health of the first grade secondary school students

Life satisfaction in relation to psychosocial school and other factors.

Life satisfaction in relation to psychosocial school and other factors.</p

Logistic regression analysis of factors related to life satisfaction among students.

Logistic regression analysis of factors related to life satisfaction among students.</p

Psychosomatic health complaints in relation to psychosocial school and other factors.

Psychosomatic health complaints in relation to psychosocial school and other factors.</p

Symptoms of depression in relation to psychosocial school and other factors.

Symptoms of depression in relation to psychosocial school and other factors.</p