Engineering Challenges in Karst

Anisotropy and heterogeneity of karstified rocks make them the most problematic media for various interventions which are needed in engineering practice. The long history of attempts to adapt karstic nature to human needs started with the utilization of karstic aquifers: tapping large springs, transferring their waters to the long distances, improving minimal flows or capturing fresh water in coastal areas. During the 20th century the number of other challenges such as building dam and reservoirs, and constructing roads and railways, bridges, tunnels, new settlements open a new era in engineering works but also in collecting new knowledge and experience for the karstology and hydrogeology sciences. Today, almost no engineering projects can be implemented without a proper environmental impact assessment, which establishes a better balance between human and ecological needs.Inženirski izzivi v KrasuAnizotropija in heterogenost zakraselih kamnin sta lastnosti, ki povzročata, da so te najbolj problematičen medij za različne posege, ki so potrebni v inženirski praksi. Dolga zgodovina poskusov, da bi prilagodili kraško naravo človekovim potrebam se je začela z izrabo kraških vodonosnikov: izkoriščanje velikih izvirov, prenos vode na dolge razdalje, poviševanje minimalnih pretokov ali zajemanje vode na obalnih območjih. V 20. stoletju je število drugih izzivov, kot so gradnja jezov in rezervoarjev, cest in železnic, mostov, predorov, novih naselij odprla novo obdobje v inženirstvu. Poleg tega je botrovala zbiranju novih krasoslovnih in hidrogeoloških znanj in izkušenj. Danes skoraj noben inženirski projekt ne more biti izveden brez ustrezne presoje vplivov na okolje, kar vzpostavlja boljše ravnotežje med človekovimi in ekološkimi potrebami

Učestalost pojedinih oboljenja akropodijuma muznih krava u Srbiji

The research included 520 dairy cows on 64 mini-farms in mountainous Serbian areas, with the goal to acquire an insight on acropodium diseases frequency in dairy cows, as well as distribution of hoof alterations. In 56.25% of farms, animals were kept tied in the stable, while 43.75% were grazing regularly or occasionally. Only 10.94% of farms were free of hoof acropodium alterations. Extremely bad hygienic conditions were noted in 18.75% of farms, where 74.01% of animals had acropodium lesions. Based on clinical analysis of 520 dairy cows, 388 of them were diagnosed with acropodium alternations: overgrown hooves (in 21.91% of animals), shoe-like hooves (7.22%), scissors-like (17.27%) and spiral hooves (8.76%). Wounded acropodium skin was diagnosed in 1.8%, interdigital phlegmon in 9.02%, aseptic pododermatitis in 3.61%, digital dermatitis in 4.89%, interdigital dermatitis in 3.09%, hoof ulcer in 3.35%, interdigital blister in 4.89%, hollow hoof wall in 6.18%, horn wall rupture in 0.51%, heel abscess in 3.09%, tendovaginitis in 3.85% and crown joint displacement in 0.26% of animals. We found no pathological lesions of the acropodium in 132 animals (25.38%).U ovom istraživanju klinički je ispitano 520 grla na 64 mini farme u brdsko- planinskom području Srbije, sa ciljem da se dobije uvid u učestalost oboljenja akropodijuma muznih krava kao i zastupljenost pojedinih alteracija. U 56,25% domaćinstava grla su bila stalno vezana a u 43,75% se redovno ili povremeno dopušta puštanje na pašu. Na samo 10,94% farmi nisu ustanovljene nikakve alteracije akropodijuma. Izrazito loši higijenski uslovi su evidentirani u 18,75% domaćinstava I tu je 74,01% imalo neku leziju akropodijuma. Na osnovu kliničke analize svih 520 muznih krava , kod 388 su ustanovljene sledeće alteracije akropodijuma: prerasle papke u 21,91% slučajeva, papučaste u 7, 22%, makazaste u 17,27% a spiralne u 8,76% grla. Rane na koži akropodijuma su evidentirane u 1,80%, aseptični pododermatitis u 3,61%, interdigitalna flegmona u 9,02%, digitalni dermatitis u 4,89%, interdigitalni dermatitis u 3,09%, čir papka u 3, 3,35%, međupupčani žulj u 4,89% slučajeva, šuplji zid u 6,18% slučajeva, prsnuće zida rožine u 0,51%, apsces pete u 3,09%, tendovaginitis u 3,85% i iščašenje krunskog zgloba u 0,26% grla. Bez patoloških lezija na akropodijumu je bilo 132 životinje (25,38%)

Utjecaj intraabdominalnog tlaka na osnovne vitalne funkcije i ishod liječenja

The purpose of the study was to point to the importance of measuring intra-abdominal pressure (IAP) and of early recognition of the consequences of increased IAP on basic vital functions. Measurement of IAP via urinary bladder was conducted every 12 hours in 70 surgical patients with acute abdominal syndromes not previously operated on. Based on the measured IAP values, all patients were divided into groups of patients with normal IAP values (n=20) and patients with increased IAP values (n=50) . Vital functions and basic laboratory analysis were monitored and the values obtained were compared with IAP in both patient groups. A statistically significant difference was found in body weight, body mass index, urine output, creatinine, urea, heart rate, partial pressure of oxygen (PaO2) and partial pressure of carbon dioxide (PaCO2) between patients with normal and increased IAP values. The increase in IAP values was found to be associated with an increase in PaCO2, respiratory rate, peak inspiratory pressure, central venous pressure, heart rate, Acute Physiology, Age and Chronic Health Evaluation II score, mortality rate, creatinine and urea values, and number of days of treatment in the intensive care unit. At the same time, the values of PaO2, blood oxygen saturation, diuresis and abdominal perfusion pressure were declining. IAP measurement is an old, cost-effective, reliable technique that is easy to perform and should be applied in all high risk patients.Cilj studije bio je ukazati na značenje mjerenja intraabdominalnog tlaka (intra-abdominal pressure, IAP) i ranog prepoznavanja promjena osnovnih vitalnih funkcija, koje su posljedica povećanja IAP. Mjerenje IAP je provedeno kroz mokraćni mjehur svakih 12 sati kod 70 bolesnika s akutnim abdominalnim sindromom koji nisu prethodno operirani. Na osnovi izmjerenih vrijednosti IAP bolesnici su podijeljeni u skupinu s normalnim vrijednostima IAP (n=20) i skupinu s povećanim vrijednostima (n=50). Praćenjem osnovnih vitalnih funkcija i laboratorijskih analiza dobivene vrijednosti uspoređivane su u odnosu na IAP u objema skupinama bolesnika. Statistički značajna razlika između bolesnika s normalnim i onih s povišenim IAP utvrđena je za tjelesnu težinu, indeks tjelesne mase, diurezu, vrijednosti kreatinina, ureju, srčanu frekvenciju, parcijalni tlak kisika (PaO2) i parcijalni tlak ugljičnog dioksida (PaCO2). Također je zapaženo da su s porastom IAP rasle i vrijednosti PaCO2, broja respiracija, vršnog inspiracijskog tlaka, centralnog venskog tlaka, srčane frekvencije, akutna fi zio loška, starosna i kronična evaluacija zdravlja II (Acute Physiology, Age and Chronic Health Evaluation, APACHE), stopa smrtnosti, vrijednosti ureje i kreatinina te broj dana liječenja u jedinici intenzivnog liječenja, dok su vrijednosti PaO2, zasićenje hemoglobina kisikom, diureza i abdominalni perfuzijski tlak bili u opadanju. Mjerenje intraabdominalnog tlaka je stara, jeftina, pouzdana metoda, jednostavna za izvođenje kod svih visoko rizičnih bolesnika

Comparative anatomical investigation of five Artemisia L. (Anthemideae, Asteraceae) species in view of taxonomy

Comparative anatomical analysis of vegetative organs has been conducted on Artemisia campestris L., A. absinthium L., A. arborescens L., A. judaica L. and A. herba-alba Asso, using light microscopy, in order to examine the most important anatomical features and to find new valid taxonomic characters. Results have shown that general root, stem and leaf anatomical features and nonglandular and glandular trichomes are shared by all species. However, some characters (parenchyma sheath, which surrounded vascular bundle and extended to both epidermises, subepidermal collenchyma and the absence of secretory canals in the leaves) link together A. absinthium and A. arborescens from the same section. Some characters, as periderm and lignified pith parenchyma cells (A. campestris and A. arborescens), nonendodermal secretory canals in root cortex (A. absinthium and A. judaica) and secretory canals in the leaf phloem (A. judaica and A. herba-alba), connect species belonging to different sections. Moreover, some characters could be considered as species-specific, nonendodermal secretory canals in the root secondary phloem, triangular leaf shape on the cross section and secretory canals in the leaf parenchyma for A. campestris, secretory canals in the stem pith for A. absinthium, crystals in the pith parenchyma cells for A. arborescens and the absence of root secretory canals for A. herba-alba. Given results revealed qualitative characters, on the basis of which the studied species are anatomically distinguishable between each other, provide valuable features for better species identification and contribute to the anatomy of the genus Artemisia

Assessment of some parameters productivity and quality of populations phleum pratense l. Grown in conditions of Serbia

Phleum pratense (L.) is the important forage grass species in Serbia. The study was conducted on 20 autochthonous population of Phleum pratense (L.), originating from Western Serbia. Plant height, protein content and crude cellulose content had a high direct impact on yield. Populations of PP16, PP20, PP2 and PP9 had the significantly higher yield of the raw matter compared to all the tested population and the highest values for the other evaluated parameters, also. The average yield of crude biomass was positive statistically highly significantly correlated with plant height (r=0.87**), and positively significantly correlated with a content of crude proteins and positive non significant correlated with crude cellulose (r=0.42 ). Based on obtained values and by the appropriate choice of selection methods, we conclude that we have excellent genotypes, PP16, PP20, PP2 and PP9 for a successful selection process in order to obtain new high yielding varieties of Phleum pratense

Composition and antimicrobial activity of essential oils of artemisia judaica, a. Herba-alba and a. Arborescens from Libya

The essential oils obtained by hydrodistillation from the aerial parts of Artemisia judaica L., Artemisia herbaalba Asso. and Artemisia arborescens L. (cultivated) from Libya, were analyzed by GC and GC-MS. The antimicrobial properties were determined using the broth microdilution method against eight bacterial species: Bacillus cereus (clinical isolate), Micrococcus flavus (ATCC10240), Listeria monocytogenes (NCTC7973), Staphylococcus aureus (ATCC6538), Escherichia coli (ATCC35210), Pseudomonas aeruginosa (ATCC27853), Salmonella typhimurium (ATCC13311), Enterobacter cloacae (human isolates) and eight fungal species: Aspergillus niger (ATCC6275), A. ochraceus (ATCC12066), A. versicolor (ATCC11730), A. fumigatus (ATCC1022), Penicillium ochrochloron (ATCC9112), P. funiculosum (ATCC10509), Trichoderma viride (IAM5061) and Candida albicans (human isolate). The major constituents of A. arborescens oil were sesquiterpene hydrocarbons (47.4%). Oxygenated monoterpenes were the dominant constituents in the A. judaica and A. herba-alba oils (54.2% and 77.3%, respectively). Camphor (24.7%) and chamazulene (20.9%) were the major components in the essential oil of A. arborescens, chrysanthenone (20.8%), cis-chrysanthenyl acetate (17.6%) and cis-thujone (13.6%) dominated in the A. herba-alba oil, and the major constituents in the A. judaica oil were piperitone (30.21%) and cis-chrysanthenol (9.1%). The best antimicrobial activity was obtained for A. judaica oil and the lowest effect was noticed in A. arborescens oil. The effect of the tested oils was higher against Gram (+) than Gram (-) bacteria. All three oils showed the best antibacterial activity against Listeria monocytogenes and the lowest against Pseudomonas aeruginosa, Escherichia coli, Enterobacter cloacae, compared to streptomycin and ampicillin. All three oils showed better antifungal activities than ketoconazole, except A. arborescens oil against Aspergillus niger

Populaciona varijabilnost unutar vrste Thymus glabrescens Willd. iz Srbije - morfologija, anatomija i sastav etarskih ulja

In five indigenous populations of Thymus glabrescens Willd. collected in the region of Banat (Serbia), the variability on leaf morphological traits, leaf and stem anatomy, and composition of the essential oil was studied. The major component in the studied populations was either thymol or γ-terpinene. Distinct differentiation of populations with respect to chemical composition of essential oils might be related to spatial distribution of the studied populations. No correlations between morphology, anatomy, and essential oil yield and composition were determined. Both capitate and peltate glandular trichomes were found on calyces, whereas the latter were noticed on the abaxial and adaxial leaf surface.U pet autohtonih populacija Thymus glabrescens Willd. sakupljenih u regionu Banata, Srbija, ispitivana je varijabilnost morfoloških karakteristika lista, anatomske građe lista i stabla i sastava etarskih ulja. Glavne komponente etarskih ulja proučavanih populacija bile su timol, γ-terpinen i p-cimen. Uočena je prostorna diferencijacija populacija u odnosu na sastav etarskih ulja. Nije ustanovljena korelacija između morfoloških i anatomskih karakteristika populacija i prinosa i sastava etarskih ulja. Prisustvo i izgled žlezdanih trihoma su utvrđeni posmatranjem nadzemnih delova na svetlosnom i skening elektronskom mikroskopu. Peltatne trihome su uočene na čašici, licu i naličju lista, dok su kapitatne nađene samo na čašicama

Prospects for wider energetic utilization of subgeothermal water resources: Eastern Serbia case study

Intenzivno korišćenje fosilnih goriva širom sveta uzrok je ozbiljnih zagađenja prirode i utiče na globalno zagrevanje. Otuda je jedan od glavnih ciljeva energetske politike evropskih zemalja korišćenje efikasnije 'zelene' energije iz obnovljivih i sopstvenih izvora. Generalno, geotermalna energija predstavlja vid obnovljivih izvora energije. Ipak, i dalje se smatra da korišćenje subgeotermalne energije niske entalpije (temperature podzemnih voda od 30°C i niže) za potrebe grejanja nije u potpunosti ekonomski opravdano. Standardna tehnologija za primenu ovog vida energije zahteva velike površine pod panelima sa cevima koje provode toplu vodu i/ili upotrebu toplotnih pumpi sa visokim stepenom iskorišćenja. Razvoj kaskadne toplotne pumpe i njena šira primena omogućila bi daleko efikasniju upotrebu 'lako' dostupnih podzemnih vodnih resursa temperature između 10-30°C i stoga je u više projekata realizovanih poslednjih godina analizirana i razvijana ova tehnologija. Hidrogeološki uslovi u terenima istočne Srbije, su veoma povoljni sa aspekta eksploatacije subgeotermalnih resursa. Područje se odlikuje značajnim količinama podzemnih voda i terestičnim toplotnim tokom u okviru geoloških formacija u osnovnim geo-strukturnim jedinicama ovog regiona (Karpato-Balkanidi i Dakijski basen). Blizina urbanizovanih naselja i manjih gradova i postojanje razvijenog i centralizovanog grejanja su činjenice koje povoljno utiču na mogućnost eksploatacije subgeotermalnih vodnih resursa. Održivo korišćenje podzemnih vodnih resursa podrazumevalo bi i potrebnu termalnu rekonstrukciju i bolju izolaciju postojećih građevinskih objekata, kao i donošenje novih zakonskih propisa u Srbiji u cilju podsticaja korišćenja obnovljivih izvora energije. U području istočne Srbije, procenjene količine energije koje se mogu dobiti iz subgeotermalnih voda iznose oko 33 MWt, što bi predstavljalo oko 16% ukupnih energetskih potreba nekoliko odabranih većih naselja za koje je ova analiza vršena. I pored činjenice da se ne očekuje potpuno iskorišćenje ovog potencijala, evidentno je da je on daleko veći od 4 % koliko je u planovima energetskog razvoja predviđeno da bi moglo iznositi učešće geotermalnih vodnih resursa na nivou cele Srbije.Extensive worldwide usage of fossil energy sources causes high pollution and contributes to global warming. Hence, achieving energy independence by stimulating efficient use of energy and environmentally friendly exploitation of renewable sources is a main orientation of European countries. Geothermal energy is generally treated as a renewable and inexhaustible energy source. Nonetheless, direct use of low enthalpy subgeothermal resources, i.e. groundwater of 30.C or lower, for heating is commonly viewed as economically unjustified. To enable its usage, large panel surfaces or a high-temperature heat pump with excellent efficiency is required. The development of a cascade type heat pump and its wide application would enable more efficient utilization of widely available and easy replenished groundwater sources with temperatures of 10-30.C. The hydrogeological conditions in eastern Serbia are particularly favourable for exploitation of subgeothermal resources due to rich aquifer systems and notable terrestrial heat flow formed into the main geo-structures of the region (Carpathian-Balkan arch and Dachian basin). More intensive exploitation of subgeothermal sources additionally justifies the existence of a number of urbanized small and medium-size cities with a heating infrastructure already developed and centralized. Sustainable use of groundwater resources should be followed by thermal reconstruction of the previously constructed buildings as well as new legislation which supports and encourages development of renewable energy sources. It is estimated that the total potential thermal power which can be generated from subgeothermal waters in the study area is around 33 MWt, which corresponds to some 16 % of the total heat requirements

Prospects for wider energetic utilization of subgeothermal water resources: Eastern Serbia case study

Intenzivno korišćenje fosilnih goriva širom sveta uzrok je ozbiljnih zagađenja prirode i utiče na globalno zagrevanje. Otuda je jedan od glavnih ciljeva energetske politike evropskih zemalja korišćenje efikasnije 'zelene' energije iz obnovljivih i sopstvenih izvora. Generalno, geotermalna energija predstavlja vid obnovljivih izvora energije. Ipak, i dalje se smatra da korišćenje subgeotermalne energije niske entalpije (temperature podzemnih voda od 30°C i niže) za potrebe grejanja nije u potpunosti ekonomski opravdano. Standardna tehnologija za primenu ovog vida energije zahteva velike površine pod panelima sa cevima koje provode toplu vodu i/ili upotrebu toplotnih pumpi sa visokim stepenom iskorišćenja. Razvoj kaskadne toplotne pumpe i njena šira primena omogućila bi daleko efikasniju upotrebu 'lako' dostupnih podzemnih vodnih resursa temperature između 10-30°C i stoga je u više projekata realizovanih poslednjih godina analizirana i razvijana ova tehnologija. Hidrogeološki uslovi u terenima istočne Srbije, su veoma povoljni sa aspekta eksploatacije subgeotermalnih resursa. Područje se odlikuje značajnim količinama podzemnih voda i terestičnim toplotnim tokom u okviru geoloških formacija u osnovnim geo-strukturnim jedinicama ovog regiona (Karpato-Balkanidi i Dakijski basen). Blizina urbanizovanih naselja i manjih gradova i postojanje razvijenog i centralizovanog grejanja su činjenice koje povoljno utiču na mogućnost eksploatacije subgeotermalnih vodnih resursa. Održivo korišćenje podzemnih vodnih resursa podrazumevalo bi i potrebnu termalnu rekonstrukciju i bolju izolaciju postojećih građevinskih objekata, kao i donošenje novih zakonskih propisa u Srbiji u cilju podsticaja korišćenja obnovljivih izvora energije. U području istočne Srbije, procenjene količine energije koje se mogu dobiti iz subgeotermalnih voda iznose oko 33 MWt, što bi predstavljalo oko 16% ukupnih energetskih potreba nekoliko odabranih većih naselja za koje je ova analiza vršena. I pored činjenice da se ne očekuje potpuno iskorišćenje ovog potencijala, evidentno je da je on daleko veći od 4 % koliko je u planovima energetskog razvoja predviđeno da bi moglo iznositi učešće geotermalnih vodnih resursa na nivou cele Srbije.Extensive worldwide usage of fossil energy sources causes high pollution and contributes to global warming. Hence, achieving energy independence by stimulating efficient use of energy and environmentally friendly exploitation of renewable sources is a main orientation of European countries. Geothermal energy is generally treated as a renewable and inexhaustible energy source. Nonetheless, direct use of low enthalpy subgeothermal resources, i.e. groundwater of 30.C or lower, for heating is commonly viewed as economically unjustified. To enable its usage, large panel surfaces or a high-temperature heat pump with excellent efficiency is required. The development of a cascade type heat pump and its wide application would enable more efficient utilization of widely available and easy replenished groundwater sources with temperatures of 10-30.C. The hydrogeological conditions in eastern Serbia are particularly favourable for exploitation of subgeothermal resources due to rich aquifer systems and notable terrestrial heat flow formed into the main geo-structures of the region (Carpathian-Balkan arch and Dachian basin). More intensive exploitation of subgeothermal sources additionally justifies the existence of a number of urbanized small and medium-size cities with a heating infrastructure already developed and centralized. Sustainable use of groundwater resources should be followed by thermal reconstruction of the previously constructed buildings as well as new legislation which supports and encourages development of renewable energy sources. It is estimated that the total potential thermal power which can be generated from subgeothermal waters in the study area is around 33 MWt, which corresponds to some 16 % of the total heat requirements