Note on Polarographic Determination of +6 Uranium

A polarographic method is proposed for determination of small amounts of +6 uranium. An aqueous solution of salicylic acid (1.6 g /l), sulphuric acid (0.4% v/ v) and thymol (0.009 %) is used as supporting electrolyte. This procedure is applicable in the concentration range from 5 to 50 μg of uranium per ml. of the solution used for polarographic measurement. Total amounts of 10 μg of uranium per sample can be determined with a standard error of ± 0.8 μg

Normalne vrijednosti olova u krvi

In order to evaluate normal values of lead in blood for the local population of Zagreb and environs the concentrations of lead in blood have been determined in a random sample of 195 healthy subjects (100 men and 95 women with no previous exposure to lead. The analyses were performed by a monocolour dithizone method. Two parallel samples of blood were analysed for each subject. It was found that the lead concentrations in blood of normal persons are log-normally distributed. 60 µg/100 ml is proposed as the upper normal limit of lead concentration in blood.Radi određivanja normalnih vrijednosti olova u krvi izvršili smo analizu krvi kod 195 zdravih osoba (100 muškaraca i 95 žena) iz Zagreba i okolice, koji u svom zvanju nisu dosad bili eksponirani olovu. Analize smo izvršili jednobojnom ditizonskom metodom (Weber, Voloder, Vouk, Arh. hig. rada, 3 (1952) 296). U području od 10-500 µg Pb/100 ml krvi preciznost te metode iznosi od ± 4,6 µg do ± 5,6 µg (preračunano po 100 ml krvi). Taj se podatak odnosi na aritmetičku sredinu rezultata dviju paralelnih analiza istog uzorka. Za svakog ispitanika izvršili smo po dvije paralelne analize. Za pojedinu analizu potrebno je 5 mi krvi. Našli smo, da su koncentracije olova u krvi kod neeksponiranih osoba raspodijeljene logaritamski normalno. Kao gornju granicu normalnih vrijednosti uzeli smo gornju 90%-nu granicu tolerancije (koeficijent pouzdanosti 0.95). Tako definirane normalne vrijednosti iznose za ukupni uzorak 60 µg/100 ml. Našli smo također. da stanovnici sela imaju statistički značajno niže vrijednosti olova u krvi nego stanovnici grada, ali te razlike nemaju praktične vrijednosti za dijagnozu profesionalne ekspozicije olovu

Eksperimentalna plinska komora

There are essentially two methods for preparing known concentrations of gases or vapours in air: the static and the dynamic method. The static method is more reliable. However, there is a serious drawback to the static method: the chambers used for this purpose are expensive. As such equipment is rather rare in European industrial hygiene laboratories it might be of interest to present here some data on the design and operation of an experimental gas chamber built in the Institute of Industrial Hygiene in Zagreb.Eksperimentalna plinska komor

Sinteza ciklopentandiamin -tetra octene kiseline, novog kelata za internu dekontaminaciju radiostroncija

La synthèse de l\u27acide cyclopentane-diamine-tétraacétique (1,2-CPDTA) est décrite. Les valeurs pour les constantes de dissociation protonique et pour les constantes de stabilité de ses complexes alcalino-terreux sont données. Le 1,2-CPDTA pourrait servir pour la décontamination interne du radiostrontium.Opisana je sinteza ciklopentandiamin-(1,2)-tetraoctene kiseline (1,2-CPDTA). Dane su vrijednosti za konstante disocijacije kao i za konstante stabilnosti kompleksa Ca+2 i Sr+2 s tom supstancijom. koja bi mogla poslužiti za internu dekontaminaciju 90Sr

Određivanje malih količina žive u biološkom materijalu

A simple method is described for the digestion of biological material containing mercury. The procedure is based on complete volatilization of mercury and subsequent absorption in an aqueous solution of potassium permanganate and sulphuric acid. Mercury ions are determined with dithizone using the reversion method. The statistical treatment of the calibration line shows that the proposed method is sufficiently sensitive and precise for toxicological work.Opisana je jednostavna metoda za mineralizaciju biološkog materijala, koji sadržava živu. Postupak se osniva na isparivanju žive i apsorpciji isparene žive u vodenoj otopini kalijum permanganata i sumporne kiseline. Nakon mineralizacije živini ioni se određuju pomoću ditizona (reverziona metoda). Statistička obrada baždarnog pravca pokazuje, da je predložena metoda dovoljno osjetljiva i precizna za toksikološki rad

Determination of lead in blood

Opisana je »jednobojna« metoda za određivanje malih količina olova u krvi s pomoću ditizona. Glavne razlike između predložene metode i uobičajenih postupaka su ove: 1. Ekstrakcija olova vrši se kod razmjerno visoke pH vrijednosti (10,5), 2. željezo se uklanja nakon mineralizacije krvi, a prije ekstrakcije ditizona. Za odstranjivanje željeza upotrebljen je kupferon. Baždarne krivulje obrađene su statistički. Rezultati pokazuju, da je tako modificirana ditizonska metoda pouzdana, osjetljiva i precizna. Standardna pogreška pojedinog određivanja nije veća od ± 7 µg za koncentracije olova od 25 do 500 µg/100 ml krvi, ako se mjerenje ekstinkcije vrši Beckmanovim spektralnirn fotometrom kod valne dužine od 520 mµ. Ako paralelno analiziramo po dva uzorka iste krvi, standardna se pogreška može smanjili na ± 5 µg.A »mono-colour« dithizone method for determination of lead in blood is described. The main points in which the proposed method differs from the usual dithizone methods are the following: (1) the extraction of lead with dithizone solution is performed at rather high pH values (10.5), (2) the iron is removed after mincra lization of blood by means of a 2% aqueous cupferron solution. The modification (I) increases the sensitivity of the method and at the same time dispenses with the necessity of washing lead-dithizonate solution to remove the excess dithizone before measuring the extinction. The cupferron extraction eliminates all the possible sources of error which are connected with the presence of iron. The statistical treatment of calibration curves showed that the proposed method is reliable, sensitive and precise. The standard error of a single determination is not more than ±7 µg for lead concentrations from 25 to 500 µg per 100 ml blood if the measurement of the optical density is performed with Beckman spectrophotometer at 520 mµ. If two parallel determinations arc made in each analysis the standard error may be reduced to ±5 µg

Lead in the drinking water in the city of Zagreb

Metodom inversne voltammetrije (DPASV) na visećoj živinoj kapi određene su masene koncentracije olova u pitkoj vodi (iz vodovoda kao i iz nekoliko privatnih bunara) na području grada Zagreba. Prosječna vrijednost za vodovodnu vodu iznosila je (1,3 ± 0,3 µg/L, što je znatno ispod dopuštenih granica; bunarske su vode sadržavale višestruko veću (iako još uvijek dopustivu) koncentraciju olova, vjerojatno zbog okolnog onečišćenja. Jednostavna metoda sa živinom kapi dovoljno je osjetljiva i pouzdana za rutinsko praćenje koncentracije olova.Lead concentrations in drinking water (both from the municipal water supply and some wells) in the city of Zagreb were determined by differential kulse anocid stripping voltammetry (DPASV) using a hanging mercury drop electrode. The average lead concentration in the municipal water was found to be (1.3 ± 0.3) µg/L, while well waters contained considerably higher (though still permissible) amounts of lead

PEDL: extracting protein-protein associations using deep language models and distant supervision

MOTIVATION: A significant portion of molecular biology investigates signalling pathways and thus depends on an up-to-date and complete resource of functional protein-protein associations (PPAs) that constitute such pathways. Despite extensive curation efforts, major pathway databases are still notoriously incomplete. Relation extraction can help to gather such pathway information from biomedical publications. Current methods for extracting PPAs typically rely exclusively on rare manually labelled data which severely limits their performance. RESULTS: We propose PPA Extraction with Deep Language (PEDL), a method for predicting PPAs from text that combines deep language models and distant supervision. Due to the reliance on distant supervision, PEDL has access to an order of magnitude more training data than methods solely relying on manually labelled annotations. We introduce three different datasets for PPA prediction and evaluate PEDL for the two subtasks of predicting PPAs between two proteins, as well as identifying the text spans stating the PPA. We compared PEDL with a recently published state-of-the-art model and found that on average PEDL performs better in both tasks on all three datasets. An expert evaluation demonstrates that PEDL can be used to predict PPAs that are missing from major pathway databases and that it correctly identifies the text spans supporting the PPA. AVAILABILITY AND IMPLEMENTATION: PEDL is freely available at https://github.com/leonweber/pedl. The repository also includes scripts to generate the used datasets and to reproduce the experiments from this article. CONTACT: [email protected] or [email protected]

Cellular responses of microcolonial rock fungi to long-term desiccation and subsequent rehydration

Melanised rock-inhabiting fungi are astonishingly resistant to environmental stresses. Also known as micro-colonial fungi (MCF), they are ubiquitous and even colonise bare rocks in deserts. To survive in nutrient poor and extremely stressful conditions, MCF have reduced morphogenetic complexity to a minimum, and rely on a broad spectrum of stress protection mechanisms. Although visual signs of carotenoid presence are masked by heavily melanised black cell-walls, we were able to isolate and characterise a variety of carotenoids (ß-carotene, ζ-carotene, phytoene, torularhodin and torulene) in the rock-inhabiting, relatively fast-growing strain A95. The desiccation/rehydration stress response was used to measure the ability of A95 to adapt to slow or fast changes in external conditions. Revival of MCF after prolonged desiccation and rehydration was documented by biochemical (analyses of lipids and protective pigments), cultivation, and microscopic methods. Survival of MCF is enhanced when desiccation is rapid and mycostasis is instant rather than following prolonged periods of low metabolic activity