Magnetic Storms and their Influence on navigation

U radu se prikazuju karakteristike Sunčevih i Zemljinih magnetskih polja, njihova međusobna povezanost, ali i njihove anomalije. Broj Sunčevih pjega, koje se povećavaju i smanjuju u nejednakim ciklusima, odgovara broju registriranih magnetskih oluja na Zemlji. Sunčeve plazma-zrake koje izbijaju iz Sunčevih pjega uzrokuju porast broja solarnih vjetrova i pri tome utječu na geomagmetsko polje i Zemljinu atmosferu. Jedan primjer takve uzročne veze bila je najžešća magnetska oluja koja se pojavila u tijeku posljednja dva Sunčeva ciklusa. Trajala je od 28. listopada do 02. studenoga 2003. godine. Uspješna plovidba ovisi o uzimanju u obzir svih promjena na Zemlji koje nastaju zbog promjena na Suncu.This article presents the nature of the Sun’s and Earth’s magnetic fields, their mutual connection and anomalies. The number of sunspots, that increase and decrease in unequal cycles, correspond to the number of registered magnetic storms on the Earth. The Sun’s plasma streams that shoot out from the sunspots cause an increase in the solar winds and in doing so they affect the geomagnetic field and the Earth’s atmosphere. One example of such a causal connection was the most extreme magnetic storm that has occurred during the last two Sun Cycles. It lasted from October 28th to November 2nd 2003. Successful navigation depends on taking into consideration all the changes on the Earth that arises from changes on the Sun

The effect of aminoguanidine, an inducible nitric oxide synthase inhibitor, on AlCl3 toxicity in the rat hippocampus

The presented experiment was carried out to determine the effectiveness of the inducible nitric oxide synthase inhibitor - aminoguanidine in modulating the toxicity of aluminum chloride on the nitrite levels, malondialdehyde concentration, reduced glutathione content, as well as cytochrome c oxidase activity of Wistar rats. The animals were killed 3 h and 30 days after treatment and the hippocampus was removed. The biochemical results show that aluminum acts as a pro-oxidant, while aminoguanidine exerts an antioxidant action in aluminum chloride-treated animals. We have also applied immunohistochemical techniques to identify iNOS expression after the treatment. Our data suggest that aminoguanidine can be effective in the protection of toxicity induced by aluminum chloride.U eksperimentu je određivana efikasnost inhibitora inducibilne forme azot oksid sintaze - aminogvanidina, u modulaciji toksičnosti aluminijum hlorida na nivo nitrita, koncentraciju malondialdehida, sadržaj redukovanog glutationa, kao i aktivnost citohrom c oksidaze kod Wistar pacova. Životinje su dekapitovane 3 časa i 30 dana nakon odgovarajućeg tretmana i izolovan je hipokampus. Rezultati dobijeni na biohemijskom nivou pokazuju da aluminijum deluje kao pro-oksidant, dok aminogvanidin pokazuje antioksidativno dejstvo kod životinja tretiranih aluminijum hloridom. Pored toga, korišćene su i imunohistohemijske tehnike za identifikaciju iNOS ekspresije, 3 časa nakon primene odgovarajućeg tretmana. Naši rezultati pokazuju da aminogvanidin može sprečiti toksičnost indukovanu aluminijum hloridom.nul

Faktori povezani sa sindromom izgaranja kod profesionalaca u farmaceutskoj industriji i marketingu

Certain authors describe some professions in the healthcare industry as the more susceptible ones to developing a burnout syndrome, while others suggest psychosocial aspects of the workplace as the primary cause in its creation, but not the aspects of the job itself. The main objective of the research was to investigate which specific factors were associated with the burnout syndrome among professionals working in pharmaceutical manufacturing industry and marketing. The study was conducted in June of 2016 as a cross-sectional study and it included 75 university educated professionals from the area of pharmaceutical industry and marketing employed in several local as well as internationally renowned pharmaceutical companies located in Belgrade. The participants were surveyed anonymously. The instruments used in the study were: a general socio-demographic questionnaire, an assertiveness self-evaluation questionnaire and the Maslach Burnout Inventory. An analysis of the responses in the burnout syndrome self-evaluation questionnaires showed that the highest level of burnout was expressed through reduced personal accomplishment (53%). The average assertiveness scores were the lowest in the individuals who demonstrated the highest level of emotional exhaustion (p=0.003), depersonalization (p=0.004), and the highest inefficiency on professional accomplishment scale (p=0.001). A statistically significant difference was observed in frequency and extent of emotional exhaustion with respect to respondents' gender (x2=10.779; p lt 0.05), as well as the line of business (x2=6.493; p lt 0.05). Levels of depersonalization are influenced by: line of work (x2=5.393; p lt 0.05), age (p=0.004), total years of service (p=0.009) and years of service in the profession (p=0.006). A sense of reduced personal accomplishment is influenced by a respondents' profession (x2=10.922; p lt 0.05) and line of business (x2=7.283; p lt 0.05). The results obtained in this study might help in identifying groups at risk for developing the burnout among the pharmaceutical manufacturing industry and drug marketing professionals. They might also assist in better assessing of the significance of interpersonal interactions between the employees for the purpose of planning the measures for the burnout prevention.Pojedini autori navode da su neke profesije u oblasti zdravstvene delatnosti podložnije razvoju sindroma izgaranja, dok drugi sugerišu da karakteristike samog posla nisu najznačajniji uzročnici izgaranja na radu, već da primarnu ulogu u njegovom nastanku imaju psihosocijalni aspekti radnog mesta. Osnovni cilj istraživanja bio je da se ispita koji su faktori povezani sa sindromom izgaranja kod zaposlenih u farmaceutskoj industriji i marketingu. Ovo istraživanje je sprovedeno tokom juna 2016. godine kao studija preseka i obuhvatilo je 75 visokoobrazovanih profesionalaca iz domena farmaceutske industrije i marketinga, zaposlenih u nekoliko domaćih i renomiranih međunarodnih farmaceutskih kompanija sa teritorije Beograda. Anketiranje je bilo anonimno. Kao instrumenti istraživanja korišćeni su opšti sociodemografski upitnik, upitnik za samoprocenu nivoa asertivnosti i Maslač inventar izgaranja (eng. Maslach Burnout Inventory). Analiza odgovora iz upitnika za samoprocenu sindroma izgaranja pokazala je da se najviši stepen izgaranja ispoljava u dimenziji umanjenog ličnog postignuća 53%. Prosečne vrednosti asertivnosti bile su najmanje kod osoba sa najvišim nivoom emocionalne iscrpljenosti (p=0,003), depersonalizacije (p=0,004) i najvišim nivoom neefikasnosti na skali profesionalnog postignuća (p=0,001). Statistički značajna razlika pronađena je u zastupljenosti i izraženosti emocionalne iscrpljenosti u odnosu na pol ispitanika (x2=10,779; p lt 0,05) i oblast rada (x2=6,493; p lt 0,05). Na izraženost depersonalizacije utiču oblast rada (x2=5,393; p lt 0,05), godine starosti (p=0,004), ukupan radni staž (p=0,009) i radni staž u struci (p=0,006). Na osećaj umanjenog ličnog postignuća bitno utiču profesija (x2=10,922; p lt 0,05) i oblast rada (x2=7,283; p lt 0,05). Dobijeni rezultati mogli bi pomoći u identifikaciji rizičnih grupa za razvoj sindroma izgaranja među profesionalcima iz domena farmaceutske industrije i marketinga, kao i boljem sagledavanju značaja interpersonalnog funkcionisanja zaposlenih u cilju planiranja preventivnih mera

The process of obtaining quartz sand size fraction -0.4 + 0.05 mm for use in water glass production

The paper presents the process of quartz sand processing from the „Bijela Stijena“-Skočić deposit in the plant „Kesogradnja d.o.o.“ at Kozluk near Zvornik, Republic of Srpska. Bearing in mind the fact that this quartz sand is used for water glass production in the company „Birač“ - Zvornik or „Alumina“ Zvornik, it was necessary to meet the quality requirements prescribed by that industrial production. Thus, the required size was -0.4+0.05 mm and the Fe2O3 content was maximum of 0.04%. Based on the laboratory tests, a technological scheme for the quartz raw material valorization was conceived in the separation of the company „Kesogradnja d.o.o.“. The obtained results showed that quartz sand for water glass size fraction -0.4+0.05 mm could be obtained in the plant. Also, by introducing a magnetic concentration after washing and grading, the Fe2O3 content was reduced from 0.131% as it is in the initial sample to 0.038% which meets the required conditions from the water glass producers

Facilitated Cross-Bridge Interactions with Thin Filaments by Familial Hypertrophic Cardiomyopathy Mutations in α-Tropomyosin

Familial hypertrophic cardiomyopathy (FHC) is a disease of cardiac sarcomeres. To identify molecular mechanisms underlying FHC pathology, functional and structural differences in three FHC-related mutations in recombinant α-Tm (V95A, D175N, and E180G) were characterized using both conventional and modified in vitro motility assays and circular dichroism spectroscopy. Mutant Tm's exhibited reduced α-helical structure and increased unordered structure. When thin filaments were fully occupied by regulatory proteins, little or no motion was detected at pCa 9, and maximum speed (pCa 5) was similar for all tropomyosins. Ca2+-responsiveness of filament sliding speed was increased either by increased pCa50 (V95A), reduced cooperativity n (D175N), or both (E180G). When temperature was increased, thin filaments with E180G exhibited dysregulation at temperatures ~10°C lower, and much closer to body temperature, than WT. When HMM density was reduced, thin filaments with D175N required fewer motors to initiate sliding or achieve maximum sliding speed

ENERGY EFFICIENCY AND USE OF RENEWABLE ENERGY SOURCES IN BUILDINGS CONSTRUCTION- PERSPECTIVE OF SUSTAINABLE DEVELOPMENT

In this paper are presented the overall energy needs of the buildings and measures to improve energy efficiency in buildings. It is shown the importance of sustainable construction as one of the important segments of environmental protection and sustainable development. It is also pointed out the importance of use of renewable energy sources in the construction of energy efficient buildings

Sindrom izgaranja defektologa zaposlenih u školama za decu sa smetnjama u razvoju

Introduction. Numerous global studies as well as the studies from Serbia have indicateds the individuals professionally engaged in providing assistance to other people and who belong to the so-called "helping professions" (health workers, psychologists, pedagogists, social workers, teachers, etc.) as the professionals at a high risk for developing various psychophysical stress reactions and symptoms of a burnout syndrome. The burnout syndrome is viewed nowadays both as a social and a professional problem, and not only as a manifestation of the psychological state of an individual. Objective. The aim of this paper is to determine levels of the burnout syndrome in special education teachers working in schools for children with developmental disorders, as well as to determine a correlation between that phenomenon and socio-demographic aspects. Method. This cross-sectional study was conducted during the school year 2017/18. on a suitable sample and included 225 special education teachers from the Republic of Serbia. As research instruments, the Work-related Stress Inventory and a Questionnaire for collecting socio-demographic data were used. Results. A cross-sectional analysis of the socio-demographic aspects and the burnout syndrome has pointed to a statistically significant difference between the type of the students`disability (χ2 = 57.916; p lt 0.01) and the total length of the teachers`service (F (4) = 3.067, p = .017). Approximatelly one half of the respondents who work with students with motor skill disorders, and nearly one third of the respondents working with hearing impaired children possess the highest levels of burnout, while a logistic regression analysis has shown that professionals working in these fields have a 3.56-fold higher likelihood of manifesting high levels of burnout . Conclusion. Burnout syndrome is more pronounced in special education teachers who have been burning out due to their lengthy work engagement. And among them, at greater risk are those who work with children with motor skill disorders and hearing impairments. One should not forget one`s personal life that may affect the burnout. Living conditions, and above all an unsolved housing status therefore, show a closer relation with burning out.Uvod. Brojna istraživanja u svetu i kod nas su pokazala da su osobe koje se profesionalno bave pružanjem pomoći drugim ljudima i koje pripadaju tzv. "pomagačkim profesijama" (zdravstveni radnici, psiholozi, pedagozi, socijalni radnici, nastavnici itd.) pod visokim rizikom za razvijanje različitih psihofizičkih stresnih reakcija i simptoma sindroma izgaranja. Sindrom izgaranja se danas posmatra kao društveni i profesionalni problem, a ne samo kao odraz psihološkog stanja pojedinca. Cilj rada. Cilj rada je utvrđivanje izraženosti nivoa sindroma izgaranja kod defektologa zaposlenih u školama za decu sa smetnjama u razvoju, kao i utvrđivanje povezanosti ove pojave sa sociodemografskim karakteristikama. Metod. Ova studija preseka sprovedena je tokom školske 2017/18. godine, na prigodnom uzorku i obuhvatila je 225 defektologa sa teritorije Republike Srbije. Kao instrumenti istraživanja korišćeni su Inventar izgaranja na radu i lista za prikupljanje sociodemografskih podataka. Rezultati. Analiza ukrštanja sociodemografskih obeležja i sindroma izgaranja pokazala je da postoji statistički značajna razlika u odnosu na tip smetnji učenika kojima defektolozi realizuju nastavu (χ2 = 57.916; p lt 0.01) i ukupan radni staž (F(4) = 3.067, p = .017). Oko polovine ispitanika koji realizuju nastavu deci sa motoričkim smetnjama i skoro trećina ispitanika koji rade sa decom sa slušnim smetnjama imaju najviše nivoe izgaranja, dok je regresiona analiza pokazala da osobe koje rade u ovim oblastima imaju 3,56 puta veću verovatnoću da manifestuju viši nivo izgaranja. Zaključak. Sindrom izgaranja je izraženiji kod defektologa kod kojih je usled dugotrajnog rada došlo do sagorevanja, a među njima su pod većim rizikom oni koji rade sa decom sa motoričkim i slušnim smetnjama. Ne treba zanemariti ni privatnu sferu života, koja utiče na izgaranje, pa tako uslovi života, pre svega nerešeni stambeni problem pokazuju veću povezanost sa izgaranjem

THE IMPROVEMENT OF THE BODY AND UDDER HYGIENE INFLUENCE ON THE MILK SAFETY AND COMPOSITION ON SMALL DAIRY FARMS IN SERBIA

The hygienic condition of dairy cows and their udders in 128 small household farms in different regions of Serbia, producing mostly milk, having 5–15 cows, a milk cooler and at least one milking machine, was evaluated by the following indicators: 1. general assessment of body cleanliness, 2. visual inspection of teats and udder base, and 3. maintenance of udder cleanliness, rated on a scale of 0 and 1 or 1 to 5. The samples were taken at each visit to the farm after cooling and tested for milk protein and fat content, somatic cell count (SCC) and the total number of microorganisms (TNM). The milk fat content was determined by the Gerber method, the protein content by the Kjeldahl method, the TNM according to the ISO 4833-1:2013 method and the SCC using Fossomatic TM. The IBM SPSS program was used for statistical data processing. Capacity, housing system, breed, milking system, number of cows, and capacity occupancy mostly had a very significant or significant impact on hygiene parameters, protein and fat content, SCC and TNM in milk. The hygiene parameters showed a continuous trend of improvement in relation to the visits. TNM mean scores increased after each visit, with significant differences between visits (F=9.63, P<0.0001). SCC scores varied very significantly between visits (F=5.17, P<0.0001). The number of visits tended to show a significant influence on the milk fat rate (F=2.221; P<0.1), but no influence on the milk protein rate (P=0.480; F=0.901). Copyright©2023 by authors, all rights reserved

The effect of aminoguanidine, an inducible nitric oxide synthase inhibitor, on AlCl3 toxicity in the rat hippocampus

The presented experiment was carried out to determine the effectiveness of the inducible nitric oxide synthase inhibitor - aminoguanidine in modulating the toxicity of aluminum chloride on the nitrite levels, malondialdehyde concentration, reduced glutathione content, as well as cytochrome c oxidase activity of Wistar rats. The animals were killed 3 h and 30 days after treatment and the hippocampus was removed. The biochemical results show that aluminum acts as a pro-oxidant, while aminoguanidine exerts an antioxidant action in aluminum chloride-treated animals. We have also applied immunohistochemical techniques to identify iNOS expression after the treatment. Our data suggest that aminoguanidine can be effective in the protection of toxicity induced by aluminum chloride.U eksperimentu je određivana efikasnost inhibitora inducibilne forme azot oksid sintaze - aminogvanidina, u modulaciji toksičnosti aluminijum hlorida na nivo nitrita, koncentraciju malondialdehida, sadržaj redukovanog glutationa, kao i aktivnost citohrom c oksidaze kod Wistar pacova. Životinje su dekapitovane 3 časa i 30 dana nakon odgovarajućeg tretmana i izolovan je hipokampus. Rezultati dobijeni na biohemijskom nivou pokazuju da aluminijum deluje kao pro-oksidant, dok aminogvanidin pokazuje antioksidativno dejstvo kod životinja tretiranih aluminijum hloridom. Pored toga, korišćene su i imunohistohemijske tehnike za identifikaciju iNOS ekspresije, 3 časa nakon primene odgovarajućeg tretmana. Naši rezultati pokazuju da aminogvanidin može sprečiti toksičnost indukovanu aluminijum hloridom.nul