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Yugoslav science during the Cold War (1945–1960): socio-economic and ideological impacts of a geopolitical shift
Get PDFTwo ideological views on science dominated the Cold War era: one of a free and apolitical
science, and the other emphasizing partisanship in science, associated with the Western and
Eastern Blocs, respectively. This study offers a specific perspective of important elements
belonging to these scientific positions, as it reveals their entanglement with geopolitical and
socioeconomic processes of the (semi)peripheral Yugoslav socialist system during the Cold
War period. After the Second World War, and before its break with the USSR in 1948,
Yugoslavia tended to emulate Soviet ideology in all aspects of society, including science. In
the period following this break, the Yugoslav socialist regime, at least initially, leaned heavily
toward the Western Bloc. By comparing Yugoslav science before and after the break with the
USSR, this study provides insight into the consequences of the geopolitical shift and socioeconomic transition of the Yugoslav socialist system, primarily in terms of the model of
scientific organization, financing, and scientific discourse. Exposed to the dynamics of
decentralization and, to a larger extent than before, market forces, Yugoslav socialism after
the break with the USSR adopted a specific form, namely Socialist Self Management. Herein, I
show that this led to the emergence of novel organizational and discursive tendencies in
Yugoslav science, which were compatible with certain aspects of the perspective of science
as ‘pure’, autonomous, and apolitical
Removal of hydrophilic, hydrophobic, and charged xenobiotic organic compounds from greywater using green wall media
Get PDFGreen walls offer a novel on-site approach for greywater treatment and reuse in densely build urban environments. However, they need to be engineered for effective removal of a wide range of emerging contaminants such as xenobiotic organic compounds (XOCs), which may be present in greywater due to extensive use of personal care products and household chemicals. This study used laboratory column design and batch experiments to investigate the performance of three lightweight green wall media (coco coir, zeolite, and perlite) and their mixture in three different combinations for the removal of twelve XOCs, covering wide range of hydrophilic, hydrophobic, and charged pollutants in greywater. The experiments were designed to assess the removal of targeted XOCs under different operational condition (i.e., hydraulic loading, infiltration rate, drying) and uncover the dominant mechanisms of their removal. Results showed excellent removal (>90%) of all XOCs in coco coir and media mix columns at the start of the experiment (i.e., fresh media and initial 2 pore volume (PV) of greywater dosing). The removal of highly hydrophobic and positively charged XOCs remained high (>90%) under all operational conditions, while hydrophilic and negatively charged XOCs exhibited significant reduction in removal after 25 PV and 50 PV, possibly due to their low adsorption affinity and electrostatic repulsion from negatively charged media. The effect of infiltration rate on the removal of XOCs was not significant; however, higher removal was achieved after 2-weeks of drying in coco coir and media mix columns. The dominant removal mechanism for most XOCs was found to be adsorption, however, a few hydrophilic XOCs (i.e., acetaminophen and atrazine) exhibited both adsorption and biodegradation removal processes. While findings showed promising prospects of unvegetated media for removing XOCs from greywater, long term studies on vegetated green wall systems are needed to understand any synergetic contribution of plants and media in removing these XOCs
Nitrification potential of daily-watered biofiltration designs for high ammonium wastewater treatment
No full textThe vegetated biofiltration systems (VBS), also known as bioretentions or rain gardens, are well-established technology for treatment of urban stormwater and recently greywater, offering multiple benefits to urban environments. However, the impact of high ammonium strength wastewater (60 mg/L) on the nitrification process in these systems is not well understood. Hence, a laboratory-based column study was conducted to uncover dominant nitrification mechanisms, based on the learnings from similar onsite wastewater treatment systems. The experimental columns tested the effect of contact time (filter media depth, 150 mm, 300 mm and 700 mm), media oxygenation (active and passive) and alkalinity/pH (marble chips 5 % weight), as well as optimal operational conditions (inflow loading, concentrations, and dissolved oxygen (DO)). All nitrogen species (NH4+, NO3−, NO2−), chemical oxygen demand (COD) and physical parameters (DO, pH, electrical conductivity) were monitored across seven events over thirteen weeks. The results show that dosing with 30 and 60 mg/L of NH4+ resulted in 700 mm sand column depth to perform almost complete nitrification of NH4+ to NO3− (< 90 %), while 300 mm designs achieved partial nitrification of NH4+ to NO2−, likely due to limited contact time and inefficient nitrite oxidizing bacteria activity. Nitrification potential of all designs further supported that appropriate aerobic contact time is necessary for effective nitrification. Inflow concentration of NH4+ and DO did not significantly impact nitrification performance, while reducing daily volume loading reduced NO3− and NO2− leaching. Active and passive aeration and alkalinity buffering did not positively affect ammonium removal. While there is a potential to apply both nitrification-denitrification and anammox processes to future VBS design, further understanding of aeration and alkalinity on microbially driven nitrification processes is needed
Impact of plastic pollution on soil biological activity in white truffle habitats in the large river plains in Serbia
Get PDFThe impact of plastic pollution on forest soil biota is an emerging research area. There are knowledge gaps on a forest microbiome composition and activity as effected by wild waste deposition in forest ecosystems located on white truffle (Tuber magnatum Pico) habitat areas. Particles of plastic materials decompose into micro-plastic particles and are responsible for many changes in the soil physicochemical characteristics, including porosity, enzymatic activities, microbial activities, plant growth. One of the first investigations of plastic and microplastic (MP) in the soil on the territory of Serbia is currently underway and is being carried out within the project "Evaluation of the Microplastic in the Soils of Serbia - EMIPLAST - SoS". The research sites are located on the alluvial plains of the largest rivers in Serbia, which are the habitats of the white truffle.
Forest sites visibly polluted and non-polluted by plastic materials were sampled and analysed for soil main chemical, physical and biological properties. Potentially mineralizable soil organic carbon was measured in a long-term incubation of soil samples with sequential measurement of the emitted CO2 flax by alkali trap method.
Preliminary results showed that some soil properties such as pH, electrical conductivity, total C and N, CEC and mechanical composition are significantly affected by the presence of plastic materials. Generally, polluted sites showed elevated microbial respiration and the rates of C mineralization. For the Danube and Morava River basin the differences were significant, while for the Sava river basin the difference wasn’t significant. In order to establish the level of the negative impact of microplastics on soil properties and microbial activity in the longer term, the study is ongoing
Characterisation of Mung bean (Vigna radiata L.) seeds using fluorescence spectroscopy and multivariate analyis
Get PDFMung bean (Vigna radiata L.) is a leguminous plant cultivated mainly in south-east Asia and used as an ingredient in local cuisine. Its principal nutritional value is contained in its constituents such as starch, proteins, (poly)phenols, and natural antioxidants. Fluorescence spectroscopy is increasingly used as a method of choice for food analysis; due to the presence of different fluorophores originating from aromatic amino acids and secondary metabolites, it is useful for proteins and phenolics detection. In this study, the total protein and phenolic contents of mung bean seed extracts were determined using the Bradford method and Folin–Ciocalteu (FC) reagent, respectively. Antioxidant activity was determined using DPPH (2,2-Diphenyl-1-picrylhydrazyl) assay. Fluorescence spectra were recorded for a series of excitation-emission wavelengths. Further, we used the multivariate analysis on the recorded excitation-emission fluorescence matrix of the studied samples. The results showed the presence of three different fluorescence components, with the position of the emission maximum corresponding to the fluorophore of proteins (component 1 with excitation/emission peak maxima at Ex 290/Em 345 nm) and phenolics (component 2 - Ex 295/Em 395 nm and component 3 - Ex 350/Em 450 nm). This fluorescence-based method could be a useful approach for estimating the nutrient properties of leguminous food
Changes in Mn availability and soil acidity in Albic Retisol limed with dolomite screenings of various sizes and doses: A long-term microfield experiment in the north-western Russia
No full textLiming of acidic soils is associated with various processes in the soil, including
the availability of nutrients for plants. The vector and extent of these changes
depend, inter alia, on the type of lime material and the doses used. Particularly, excessive liming can trigger a deficiency of manganese for crops. A long-term microfield experiment (13 test years) was carried out on Albic Retisols reclaimed with the dolomite particles of various sizes as a by-product of stone processing quarries. Ten treatments including various sized dolomite particles and their combinations, as well as traditional limestone flour on the background of NPK fertilizer were studied for the changes in soil acidity indicators (exchangeable acidity, pH; hydrolytic acidity, Hy; total acidity, Htot) and manganese availability. The amount of acidic components passing into the extract of 1N KCl was insufficient to reveal a dependency between the exchangeable acidity and the content of mobile manganese in the soil of most treatments limed with dolomite particles of various sizes. However, the relationship between the content of mobile Mn in soils and the value of hydrolytic acidity was proved by paired linear regressions. Regardless of the dose and size of dolomite particles added, the soil was highly and moderately supplied with plant available manganese during the entire study perio
Water–Rock Interactions across Volcanic Aquifers of the Lece Andesite Complex (Southern Serbia): Geochemistry and Environmental Impact
No full textThe study of aquifers of the Lece andesite complex (LAC) and its surroundings yielded a new procedural stepwise analysis that allowed the assessment of the origin of elements, particularly in areas affected by both anthropogenic and natural influences. The methodology uses the mineralogical composition of the rocks, including the elements available in rocks and groundwater. This study analyzes the element ratios B/Cl−, Na+/Ca2+, Ca2+/Mg2+, HCO3−/Cl−, and Na+/Na+ + Cl−; the correlations are coupled with a statistical analysis. In addition to reevaluating the already published water content, we provide an important new dataset. The results show that the main source of the water contamination with the elements B, F, U, As, Cu, Fe, Zn, Co, and Ni is the processes occurring at the contact between the groundwaters and non-altered/altered (propylitized) andesite rocks. This is also observed in the waters extracted from crystalline schists. The results may help develop an efficient use and assessment of the qualitative water potential of the LAC reservoirs. Similarly, the results highlight the applicability of the groundwaters, facilitating their regional research and use, further encouraging new initiatives for the preservation and protection of human and animal health
The formation of Fe3+ ‑doxycycline complex is pH dependent: implications to doxycycline bioavailability
No full textThe interactions of drugs with iron are of interest in relation to the potential effects of iron-rich foods and iron supplements
on sorption and bioavailability. Doxycycline (DOX), a member of the tetracycline class of broad-spectrum antibiotics, is
frequently administered by oral route. In the digestive tract, DOX can be exposed to iron at different pH values (stomach pH
1.5–4, duodenum pH 5–6, distal jejunum and ileum pH 7–8). In relation to this, we analyzed the impact of pH on Fe3+-
DOX
complex formation. The optimal conditions for Fe3+-
DOX complex formation are pH = 4 and [
Fe3+]/[DOX] = 6 molar ratio.
HESI-MS showed that Fe3+-
DOX complex has 1:1 stoichiometry. Raman spectra of Fe3+-
DOX complex indicate the presence
of two Fe3+-
binding sites in DOX structure: tricarbonylamide group of ring A and phenolic-diketone oxygens of BCD
rings. The Fe3+-
DOX complex formed at pH = 4 is less susceptible to oxidation than DOX at this pH. The increase of pH
induces the decomposition of Fe3+-
DOX complex without oxidative degradation of DOX. The pH dependence of Fe3+-
DOX
complex formation may promote unwanted effects of DOX, impeding the absorption that mainly takes place in duodenum.
This could further result in higher concentrations in the digestive tract and to pronounced impact on gut microbiota
The Impact of Copper Ions on the Activity of Antibiotic Drugs
No full textCopper (Cu) is an essential trace metal and its concentration in body plasma is tightly
regulated. An increase in Cu concentration in body fluids is observed in numerous pathological
conditions, including infections caused by microorganisms. Evidence shows that Cu ions can
impact the activity of antibiotics by increasing efficiency or diminishing/neutralizing antibiotic
activity, forming complexes which may lead to antibiotic structure degradation. Herein, we represent
the evidence available on Cu–antibiotic interactions and their possible impact on antimicrobial
therapy efficiency. So far, in vitro studies described interactions between Cu ions and the majority of
antibiotics in clinical use: penicillins, cephalosporins, carbapenems, macrolides, aminoglycosides,
tetracyclines, fluoroquinolones, isoniazid, metronidazole. In vitro-described degradation or lower
antimicrobial activity of amoxicillin, ampicillin, cefaclor, ceftriaxone, and meropenem in the presence
of Cu ions suggest caution when using prescribed antibiotics in patients with altered Cu levels.
On the other hand, several Cu-dependent compounds with antibacterial activity including the
drug-resistant bacteria were discovered, such as thiosemicarbazones, disulfiram, dithiocarbamates,
8-hydroxiquinoline, phenanthrolines, pyrithione. Having in mind that the development of new
antibiotics is already marked as inadequate and does not meet global needs, the potential of Cu–
antibiotic interactions to change the efficiency of antimicrobial therapy requires further investigation
MONITORING, IDENTIFIKACIJA I MOLEKULARNO-GENETIČKA KARAKTERIZACIJA FITOPATOGENIH BAKTERIJA KROMPIRA (SOLANUM TUBEROSUM L.)
Get PDFU Srbiji krompir ima veliki privredni značaj i pripada vodećim ratarsko-povrtarskim kulturama.
Tokom monitoringa sprovedenog od 2015 do 2019. godine, obuhvaćeno je preko 2000 ha useva
krompira sa 16 lokaliteta. Rezultati monitoringa su ukazali na prisustvo dve bakteriozne bolesti. Mrka
trulež krtola krompira utvrđena je u 2015, 2016. i 2018. godini i kao uzročnik je identifikovana
karantinska bakterija Ralstonia solanacearum. „Crna noga“ i vlažna trulež krtola krompira, koju su
prouzrokovale bakterije Pectobacterium carotovorum, Pectobacterium brasiliense i Dickeya
dianthicola, detektovana je u 2016, 2018. i 2019. godini. U ovom istraživanju, prisustvo P. brasiliense
i D. dianthicola prvi put je zabeleženo na krompiru u Srbiji. Izolati R. solanacearum dobijeni iz 229
uzoraka sa mrkom truleži krtola bili su fenotipski homogeni, a na osnovu molekularno-genetičke
karakterizacije svrstani su u filotip II. Rezultati ispitivanja fenotipskih karakteristika izolata iz 50
uzoraka sa crnom nogom i vlažnom truleži krtola ukazali su na postojanje uzročnika iz dva roda,
Pectobacterium i Dickeya. Međutim, molekularno-genetička karakterizacija ovih izolata ukazala je
na prisustvo tri vrste, pri čemu su P. brasiliense izolati bili heterogeni, dok su P. carotovorum i D.
dianthicola izolati uglavnom bili homogeni. Metabarkoding analiza omogućila je uvid u sastav
bakterijske mikrobijalne zajednice krtola krompira sa i bez simptoma vlažne truleži, kao i
odgovarajućih zemljišta ukazujući da razvoj vlažne truleži nastaje zbog složenih interakcija između
biljnih patogena i drugih endofitnih bakterija. Biokontrolna aktivnost Bacillus amyloliquefaciens
sojeva SS-12.6 i SS-38.4 prema izolovanim fitopatogenim bakterijama je dokazana u in vitro, in situ
i in planta uslovima