104 research outputs found
Impact of the geographic factors on the transport of lead and cadmium in the air
The aim of this study is to describe the effect of geographical varieties on the transport of lead and cadmium in the air. During period between 1997- 2006, the concentrations of lead in suspended in the air at 5 measuring sites in Serbia were measured. The minimal measured daily concentrations of lead ranged from 0,42 Ī¼g/m3 (2002.) in Kraljevo. The maximal measured daily concentrations of lead to 251,8 Ī¼g/m3 (2004.) in Belgrade. During the period between 1997-2006., the concentrations of cadmium in suspended in the air at 5 measuring sites in Serbia were measured. The minimal measured daily concentrations of cadmium ranged from 0,1 Ī¼g/m3 (1999) in Kraljevo. The maximal measured daily concentrations of lead to 42,0 Ī¼g/m3 (2000) in Belgrade. Results from our experiments demonstrated that when rapid infiltration conditions or a rainstorm exist, particle-facilitated transport of contaminants is likely to the dominant metal transport pathway influenced by acid rain.Physical chemistry 2008 : 9th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 24-28 September 200
Tricarbonyltechnetium (I) labelled ligands with nso donor atom set: in vitro and in vivo evaluation
There is an increasing interest for the 99mTc labelling of biomolecules by using bifunctional chelating agents. To find new ligand, which can be linked to the small biomolecules and coordinated with technetium-99m tricarbonyl complexes, is a challenging task. The investigated NSC and NSC5 ligands allow the preparation 99mTc(I) stable complexes in high yield. The 99mTc complexes were characterized by comparing their HPLC profiles with those of the respective Re(I) compounds. Biodistribution and stability studies were carried out, including challenge with histidine. These complexes also proved to be stable in vivo and showed a very good biological behaviour. The radiochemical and biological features of the novel 99mTc complexes, as well as, the nature of the ligands, make them very promising candidates for labelling of tumour specific biomolecules.Physical chemistry 2006 : 8th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 26-29 September 200
Investigation of Cl- and So4 2- anion absorption in natural soils
In this paper, the results of vertical migration of chloride and sulphate anions in soil are presented. The soil was contaminated with NaCl and CuSO4. Anions migration were monitored during one hydrological year (425 days). The first sample was taken after 150 days and afterwards samples were taken every 50 days. Before the profile contamination physical and chemical analyses of soil have been done. The obtained results show that chloride concentration in soil was in the range from 0.67 mg/kg up to 11.92 mg/kg, while sulphate concentration was in the range from 0.65 mg/kg up to 9.79 mg/kg
Application of raw and modified clay for the removal of heavy metals from aqueous solutions
This work represents a fundamental study of the simultaneous sorption of
heavy metals from aqueous solutions by locally available raw and
mechanochemically activated natural clay. The obtained results show that
the investigated clay, as an economical and efficient sorbent, has potential
for application in the treatment of heavy-metal-contaminated wastewaters
Hydrogen storage properties of MgH(2)-diatomite composites obtained by high-energy ball milling
To investigate the effects of specific porous microstructure of diatomite on the hydrogen storage properties of MgH(2), a two-step preparation was carried out. The first step was decrepitation of MgH(2) particle size during 10 h of milling. The second step was additional 1 h of milling with diatomite. The microstructure and phase composition of materials was characterized by X-ray diffraction, whereas the powder morphology and degree of additive dispersion were analyzed by scanning electron microscopy. The hydrogen desorption behaviour of nanocomposites was investigated by differential scanning calorimetry. The results show that addition of porous diatomite structure leads to decrease in desorption temperature, since there was no other effect that can have an influence on kinetics, such as formation of the metastable gamma-phase, reduction of oxides to the native metal and/or homogeneous dispersion of the catalyst. This indicates that the microstructure of added material plays the main role in the enhancement of desorption properties of composites
Autoimunske bolesti Ŕtitaste žlezde - in vitro dijagnostika
In diagnostics of autoimmune thyroid diseases a number of in vitro methods is used to evaluate thyroid function or examine the presence of an tithyroid antibodies which may be included in pathogenesis of the disease or only represent "silent witnesses" of autoimmune processes. During the evaluation of thyroid function serum concentrations of thyroid-stimulating hormone (TSH) and thyroid hormones are determined and due to these concentrations the diagnosis of manifested or subclinical disturbances of thyroid gland is set. Detection of antibodies specific in dominant thyroid auto antigenes represents confirmation of autoimmune pathogenesis of the disease. The concentration of TSH and thyroid hormones in blood may be influenced by some diseases and drugs, so abnormal values can be detected in absence of diseases of thyroid gland. In the serum of a tested person heterophilic antibodies, rheumatoid factors or other antibodies may occur which reduce the number of specific interactions in the assay, causing increased or decreased concentrations of hormones or autoantibodies. A great number of methods used in in vitro diagnostics differs very much by sensitivity which should be considered during the interpretation of laboratory results. This study presents the most important methods used in diagnostics of autoimmune thyroid diseases.U dijagnostici autoimunskih bolesti Å”titaste žlezde koriste se brojne in vitro metode kojima se procenjuje tireoidna funkcija ili ispituje prisustvo antitireoidnih autoantitela koja mogu biti ukljuÄena u patogenezu bolesti ili samo predstavljati "neme svedoke" autoimunskog procesa. Pri proceni funkcije Å”titaste žlezde odreÄuju se serumske koncentracije tireostimuliÅ”uÄeg (TSH) i tireoidnih hormona i na osnovu njihove koncentracije postavlja dijagnoza ispoljenih ili subkliniÄkih poremeÄajafunkcije Å”titaste žlezde (hipertireoze ili hipotireoze). Potvrdu autoimunske patogeneze bolesti predstavlja detekcija antitela specifiÄnih za dominantne tireoidne autoantigene (receptor za TSH, tireoidnu peroksida zuitireoglobulin). Na koncentraciju TSH i tireoidnih hormona u krvi mogu uticati neka fizioloÅ”ka stanja, bolesti i lekovi, tako da se abnormalne vrednosti mogu detektovati i u odsustvu bolesti Å”titaste žlezde. U serumu ispitanika mogu biti prisutna heterofilna anti tela, reumatoidni faktori ili druga auto anti tela koja smanjuju broj specifiÄnih interakcija u testu prouzrokujuÄi poveÄanu ili smanjenu koncentraciju hormona ili autoantitela. Veliki broj metoda koje se koriste u in vitro dijagnostici veoma se razlikuju prema osetljivosti, Å”to treba imati u vidu prilikom interpretacije laboratorijskih rezultata. U ovom radu su prikazane najvažnije metode koje se koriste u dijagnostici autoimunskih bolesti Å”titaste žlezde: Graves-ove bolesti i Hashimoto tireoiditisa
Uticaj meteoroloŔkih parametara na koncentraciju SO2 u Obrenovcu, Srbija
In this paper, the impacts of some meteorological parameters on the SO2 concentrations in the City of Obrenovac are presented. The City of Obrenovac is located in the north-west part of Serbia on the banks of the River Sava. The observed source emission, the power plants TENT A and B are situated on the bank of the Sava River in the vicinity of Obrenovac. During the period from January to November 2006, the concentrations of sulfur dioxide in the air at 4 monitoring sites in Obrenovac were measured. It was noticed that the maximal measured daily concentrations of sulfur dioxide ranged from 1 Ī¼g m-3 (16th November, 2006) to 98 Ī¼g m-3 (29th January 2006) and lie under the maximal allowed concentration value according to the Serbian Law on Environmental Protection. The measured sulfur dioxide concentrations mostly showed characteristics usual for a daily acidification sulfur dioxide cycle, excluding the specificities influenced by the measuring site itself. Sulfur dioxide transport was recorded at increased wind speeds, primarily from the southeast direction. Based on the impact of meteorological parameters on the sulfur dioxide concentration, a validation of the monitoring sites was also performed from the aspect of their representivity.U radu su predstavljeni rezultati monitoringa koncentracije SO2 u vazduhu u Obrenovcu koji se nalazi na severozapadu Srbije na obalama reke Save. Posmatran je uticaj meteoroloÅ”kih parametara na koncentraciju SO2 emitovanog iz termoelektrana TENT A i B koji se smatraju najveÄim izvorima emisije. U periodu od januara do novembra 2006. godine praÄene su koncentracije sumpor-dioksida u vazduhu na 4 merna mesta lokalizovana na razliÄitim udaljenostima od izvora emisije. Maksimalne izmerene dnevne koncentracije sumpor-dioksida su se kretale od 1 Ī¼g m-3 (16. novembra, 2006) do 24 Ī¼g m-3 (29. januara, 2006). Izmerene promene koncentracija sumpor-dioksida uglavnom pokazuju uobiÄajene karakteristike dnevne acidifikacije ciklusa uz razlike koje potiÄu od osobenosti mernih mesta. Transport sumpor-dioksida zabeležen je pri pojaÄanom vetru prvenstveno iz jugoistoÄnog pravca. Na osnovu korelacionih odnosa izmeÄu koncentracije sumpor-dioksida i odgovarajuÄih meteroloÅ”kih parametara izvrÅ”ena je karakterizacija mernih mesta u pogledu njihove reprezentativnosti za merenje sumpor-dioksida
Uticaj meteoroloŔkih parametara na koncentraciju SO2 u Obrenovcu, Srbija
In this paper, the impacts of some meteorological parameters on the SO2 concentrations in the City of Obrenovac are presented. The City of Obrenovac is located in the north-west part of Serbia on the banks of the River Sava. The observed source emission, the power plants TENT A and B are situated on the bank of the Sava River in the vicinity of Obrenovac. During the period from January to November 2006, the concentrations of sulfur dioxide in the air at 4 monitoring sites in Obrenovac were measured. It was noticed that the maximal measured daily concentrations of sulfur dioxide ranged from 1 Ī¼g m-3 (16th November, 2006) to 98 Ī¼g m-3 (29th January 2006) and lie under the maximal allowed concentration value according to the Serbian Law on Environmental Protection. The measured sulfur dioxide concentrations mostly showed characteristics usual for a daily acidification sulfur dioxide cycle, excluding the specificities influenced by the measuring site itself. Sulfur dioxide transport was recorded at increased wind speeds, primarily from the southeast direction. Based on the impact of meteorological parameters on the sulfur dioxide concentration, a validation of the monitoring sites was also performed from the aspect of their representivity.U radu su predstavljeni rezultati monitoringa koncentracije SO2 u vazduhu u Obrenovcu koji se nalazi na severozapadu Srbije na obalama reke Save. Posmatran je uticaj meteoroloÅ”kih parametara na koncentraciju SO2 emitovanog iz termoelektrana TENT A i B koji se smatraju najveÄim izvorima emisije. U periodu od januara do novembra 2006. godine praÄene su koncentracije sumpor-dioksida u vazduhu na 4 merna mesta lokalizovana na razliÄitim udaljenostima od izvora emisije. Maksimalne izmerene dnevne koncentracije sumpor-dioksida su se kretale od 1 Ī¼g m-3 (16. novembra, 2006) do 24 Ī¼g m-3 (29. januara, 2006). Izmerene promene koncentracija sumpor-dioksida uglavnom pokazuju uobiÄajene karakteristike dnevne acidifikacije ciklusa uz razlike koje potiÄu od osobenosti mernih mesta. Transport sumpor-dioksida zabeležen je pri pojaÄanom vetru prvenstveno iz jugoistoÄnog pravca. Na osnovu korelacionih odnosa izmeÄu koncentracije sumpor-dioksida i odgovarajuÄih meteroloÅ”kih parametara izvrÅ”ena je karakterizacija mernih mesta u pogledu njihove reprezentativnosti za merenje sumpor-dioksida
Autoimunske bolesti Ŕtitaste žlezde - in vivo dijagnostika
Autoimmune thyroid disease, Graves disease and Hashimoto thyroiditis, cause changing in morphology and function of the thyroid tissue. Graves disease is characterized by an increased synthesis and release of thyroid hormones (hyperthyrosis). Hashimoto fhyroiditis is characterized by the destruction and regeneration of thyroid follicles, which are clinically expressed by symptoms of hypothyrosis. Less frequently, Hashimoto fhyroiditis is expressed by transient thyrotoxicosis (if the destruction of the thyroid gland tissue is extremely emphasized). In order to examine thyroid morphology and function, there are numerous in iga diagnostic methods. Ultrasono graphy enables the examination of the fine structure and vasculanzation of the thyroid gland, and nuclear medicine methods reflect the function of the thyroid tissue. Radioactive iodine uptake is useful in assessment of the ability of thyrocytes to uptake iodide, and scmtigraphy gives the morpho-functional picture of the thyroid gland. Scintigraphy of orbital tissue gives the insight of orbital accumulation of the activated leucocytes. Although modem imaging methods (positron emission tomography, computed tomography and magnetic resonance imaging) are very useful in assessment of nodular changes in the thyroid gland and retrostemal goiter, these techniques are not widely applied in diagnostic procedures of autoimmune thyroid diseases. In this study we reviewed in vivo diagnostic methods used in the examination of Graves disease and Hashimoto thyroiditis, we considered their significance in the investigation of pathological process in the thyroid gland and we noticed the factors which could influence the results of morphological and functional investigations of the thyroid gland.Autoimunske bolesti Å”titaste žlezde, Gravesova bolest i Hashimoto tireoiditis, prouzrokuju promenu strukture i funkcije tireoidnog tkiva. Gravesovu bolest karakteriÅ”e poveÄana sinteza i oslobaÄanje tireoidnih hormona (hipemreoza), a Hashimoto tireoiditis destrukcija i regeneracija tireoidnih folikula, koje se kliniÄki ispoljavaju simptomima hipotireoze, a ako je destrukcija tkiva Å”titaste žlezde veoma izražena, privremeno mogu da se jave i simptomi tireotoksikoze. Da bi se ispitala struktura i funkcija tireoidnog tkiva primenjuju se brojne in vivo dijagnostiÄke metode. Ultrasonografija daje uvid u finu strukturu i vaskularizaciju Å”titaste žlezde, a metode nuklearne medicine odslikavaju funkciju tireoidnog tkiva. Testom fiksacije radioaktivnog joda procenjuje se sposobnost tireocita da preuzmu jodid, a scintigrafijom se dobija morfofunkcijska slika Å”titaste žlezde. Scintigrafijom orbite kod obolelih od Gravesove bolesti ispituje se stepen infiltracije orbitalnog tkiva aktivisanim leukocitima. Iako su savremene imaging metode (pozitronska emisiona tomografija, kompjuterizovana tomografija i magnetna rezonanca) veoma korisne u ispitivanju nodoznih promena u Å”titastoj žlezdi i substemame strume, te metode nisu znaÄajnije zastupljene u dijagnostici autoimunskih tireoidnih bolesti. U ovom radu su prikazane in vivo dijagnostiÄke metode koje se koriste u dijagnostici Gravesove bolesti i Hashimoto tireoiditisa, njihov znaÄaj u ispitivanju patoloÅ”kog procesa u Å”titastoj žlezdi i faktori koji svojim dejstvom mogu da utiÄu na rezultate ispitivanja
- ā¦