Isolation of Active Substances from the Seeds of the Milk Thistle Plant (Silybum marianum) and Determination of Antioxidant Activity

Opisana je izolacija silimarina, smjese dobro definiranih flavonolignana, iz sjemena biljke sikavice (Silybum marianum). Silimarin je ekstrahiran acetonom iz deoleinizirana sjemena bez zagrijavanja. Iskorištenje je iznosilo Y = 4,1 %. Antioksidacijska aktivnost silimarina određena je na sobnoj temperaturi kolorimetrijski 2,2-difenil-1-pikrilhidrazilom (DPPH) pri λ = 515 nm. Aktivnost je određena na temelju smanjenja apsorbancije, kao rezultat promjene boje DPPH iz purpurne u žutu. Dobiveni rezultati pokazuju da je askorbinska kiselina znatno jači antioksidans od ispitivana silimarina, ali je silimarin znatno jači hvatač radikala DPPH od standarda silibinina.Isolation of silymarin, a mixture of well-defined flavonolignans, from the seeds of milk thistle (Silybum marianum) was achieved. Silymarin was extracted from defatted seed with acetone without heating; the yield was Y=4.1 %. The antioxidant activity of silymarin was determined at ambient temperature by means of a 2,2-diphenyl-1-picrylhydrazyl (DPPH) colorimetry with a detection scheme at λ= 515 nm. The activity was evaluated by the decrease in absorbance as the result of a DPPH radical color change from purple to yellow. The results obtained showed that ascorbic acid was a substantially more powerful antioxidant than silymarin, but silymarin was a significantly stronger quencher of DPPH radical than the standard silibinin

Clustering of Lyman alpha emitters at z ~ 4.5

We present the clustering properties of 151 Lyman alpha emitting galaxies at z ~ 4.5 selected from the Large Area Lyman Alpha (LALA) survey. Our catalog covers an area of 36' x 36' observed with five narrowband filters. We assume that the angular correlation function w(theta) is well represented by a power law A_w = Theta^(-beta) with slope beta = 0.8, and we find A_w = 6.73 +/- 1.80. We then calculate the correlation length r_0 of the real-space two-point correlation function xi(r) = (r/r_0)^(-1.8) from A_w through the Limber transformation, assuming a flat, Lambda-dominated universe. Neglecting contamination, we find r_0 = 3.20 +/- 0.42 Mpc/h. Taking into account a possible 28% contamination by randomly distributed sources, we find r_0 = 4.61 +/- 0.6 Mpc/h. We compare these results with the expectations for the clustering of dark matter halos at this redshift in a Cold Dark Matter model, and find that the measured clustering strength can be reproduced if these objects reside in halos with a minimum mass of 1-2 times 10^11 Solar masses/h. Our estimated correlation length implies a bias of b ~ 3.7, similar to that of Lyman-break galaxies (LBG) at z ~ 3.8-4.9. However, Lyman alpha emitters are a factor of ~ 2-16 rarer than LBGs with a similar bias value and implied host halo mass. Therefore, one plausible scenario seems to be that Lyman alpha emitters occupy host halos of roughly the same mass as LBGs, but shine with a relatively low duty cycle of 6-50%.Comment: 23 pages in preprint format, 4 figures, ApJ accepte

Photoelectron Spectra of Lignin Model Compounds

The He I photoelectron (PE) spectra of the 77 lignin subunits were measured and arranged in classes of compounds according to the following functional groups: aldehydes, ketones, alcohols, carboxylic acids, functionalized polymethyl benzenes and miscellaneous lignin subunits. In all spectra the highest occupied molecular orbital (HOMO) was assigned to a jt-orbital

Organizational readiness for co-creation of public services in the central and eastern european administrative tradition: Development of the conceptual multi-attribute decision support model

Co-creation of public services and policies is considered a promising practice of re-shaping the traditional relationship between the state and its citizens, businesses and non-governmental organizations (NGOs). Nevertheless, there are also warnings that the implementation of the process of co-creation could fail. A possible reason is that the organization is not ready or sufficiently mature to implement the process of co-creation. This paper addresses co-creation drivers and barriers identified through systematic literature review and analysis of case studies from two Central and Eastern European (CEE) countries. The aim of this paper is to provide practitioners from CEE countries with a conceptual multi-attribute decision support model for evaluating the organizational readiness for co-creation. The methodological framework consists of three steps. The first two steps, content analysis (i.e. literature review) and case-study analysis, were used to identify and analyze drivers and barriers, which are then used in the last step to develop the conceptual multi-attribute decision support model. The developed model consists of 26 attributes grouped into three categories: Capacity of the organization, drivers and barriers related to internal (public organization) co-creators, and context related drivers and barriers. The key points for practitioners are: •Co-creation drivers and barriers affect organizations at the beginning of their co-creation journey (i.e. in identifying the key co-creation success factor at the organizational level); •Co-creation drivers and barriers serve as guidance to organizations that were unsuccessful in co-creation; •The conceptual model supporting the evaluation of co-creation readiness serves as a tool to those that consider implementing co-creation; •The model offers an insight into a possible methodology for evaluation of readiness in different areas; •For practitioners from the CEE region, co-creation drivers and barriers, together with the conceptual multi-attribute decision support model supporting the evaluation of co-creation readiness, offer a roadmap to successful co-creation

Design of Microstrip Coupledline Bandpass Filter

Microstrip Bandpass Filter simulations are included in this project paper. It has a graph, a design, a top view, and a 3D projection. The Coupled-Line Microstrip Filter is built of FR-4 material with a permittivity of 4.4 and is designed for a center frequency of 2.4 GHz. The ground is 1.55mm thick, and the air is 11mm thick. 50 ohms is the characteristic impedance. This filter is attached to the two ports and is made up of parallel-coupled lines linking the two ports. All of the dimensions have been put down. S11 values should be less than -10dB, while S12 values should be more than -2dB. The filter gives an insertion of -1.7 dB, return loss of -23 dB, and bandwidth of 1.5 GHz. Designed Microstrip Coupled Line Bandpass Filter can be used for wireless and high-frequency applications. All the design and simulations of this filter are done using Sonnet Suites Software

Elemental composition of plankton exometabolites (mucous macroaggregates): Control by biogenic and lithogenic components

Among the various exometabolitic effects of marine microorganisms, massive mucilage events in the coastal zones of temperate and tropical seas are the most spectacular and environmentally important. Abundant mucilage material in the form of aggregates appears in late spring/early summer in the water column of the Adriatic Sea. These macroaggregate biopolymers originate mainly from plankton exometabolites, with both autochthonous and allochthonous components, and strongly impact the tourism, fisheries, and economy of coastal countries. In contrast to extensive studies on the structural and chemical nature of macroaggregates performed over past decades, the full elemental composition of these substances remains poorly known, which does not allow for a complete understanding of their origin, evolution, and necessary remediation measures. Here, we report the results of comprehensive analyses of 55 major and trace elements in the composition of macro aggregates collected at the surface and in the water column during massive mucilage events. Through normalization of the elemental chemical composition of the upper earth crust (UCC), river suspended material (RSM), mean oceanic plankton, and mean oceanic particulate suspended material, we demonstrate that the water column macroaggregates reflect a superposition of the signal from plankton and marine particulate matter. The surface macroaggregates were preferentially enriched in lithogenic component, and carried the signature of planktonic material. The rare earth element (REE) signal was strongly dominated by plankton and, to a lesser degree, by oceanic particulate matter, while at the same time being strongly (>80 times) impoverished compared with UCC and RSM. Taken together, the elemental composition of macroaggregates allows for distinguishing the lithogenic and biogenic impacts on the occurrence of these unique large-scale mucilage events, linked to the exometabolism of marine plankton combined with the input of allochthonous inorganic material

Molecular Imaging Mass Spectrometry

Molecular imaging mass spectrometry (IMS) is a recently developed method for direct determination of spatial distribution of biopolymers, preferably proteins on cell surface and tissues. Imaging mass spectrometry data are mainly based on Matrix-Assisted Laser Desorption/Ionization- Time of Flight (MALDI TOF). The MALDI TOF based imaging mass spectrometry was applied for determination of changes in kidney tissue of sensitive mice after poisoning with aristolochic acid I. The second application presented here were changes in the gastric tissue in mice after infection with Helicobacter pylori, as a model of gastric cancer in humans caused by this pathogen microorganism. Molecular imaging mass spectrometry can be applied in medicine, mostly for identification of candidate biomarkers for malignant and non-malignant diseases. Furthermore, imaging MS has almost unlimited capacity in agriculture, food technology and biotechnology, e. g. for monitoring, process development and quality control of manufactured tissue of animal, plant and microbial origin.Razvoj masene spektrometrije u posljednjih 20 godina i primjena ove metode u analitici makromolekula, prije svega proteina i ugljikohidrata, otvorio je nove perspektive za uporabu ove metode u medicini, biotehnologiji i ostalim biodisciplinama. Ova se metoda može primijeniti i u novim područjima, kao što su mikroelektronika, geokemija i površinska analitika, posebice nanotehnologija.1 Imaging mass spectrometry (IMS) je jedna vrsta sinteze dviju tehnika, histokemije i masene spektrometrije. Ova metoda omogućava optički prikaz rasporeda raspodjele malih i velikih molekula u uzorku, pa čak i makromolekula kao što su proteini i polisaharidi. 2 Optimalizacija masene spektrometrije, ali također i veliki napredak u razvoju instrumentacije dodatni su razlog za sve veći interes za ovu metodu u mnogim interdisciplinarnim područjima medicine, biotehnologije, ali ianorganskim tehnologijama i znanosti o materijalima (material science).1 Imaging MS daje mogućnost izravnog praćenja prostorne raspodjele molekula u stanicama ili tkivu. Za dobivanje molekularne distribucije u adekvatno pripravljenom uzorku najčešće se primjenjuju Matrix-Assisted Laser Deionisation (MALDI) Time of Flight (TOF) ili Secondary Ion Mass Spectrometry (SIMS)4. Pomoću MALDI TOF dobiva se slika prostorne raspodjele velikih molekula, prije svega proteina. Rezolucija ove metode je 25 μm, što je još uvijek nedovoljno da se prati raspored komponenata na razini stanice, ali novi instrumenti omogućavaju i bolju rezoluciju u području od oko 10 μm. SIMS je metoda koja se primjenjuje za praćenje prostorne raspodjele malih molekula, najčešće biološki aktivnih supstancija. 1,5,6 MALDI TOF je pak metoda izbora za analizu prostorne distribucije makromolekula, najčešće proteina i polipeptida. IMS se do sada primjenjivala za patološke studije i analizu biomarkera,3,7-10 za analizu tumora, kao glioblastoma,3 karcinoma debeloga crijeva,11 metastaza u jetri,12 kod praćenja promjena u moždanom tkivu kod Alzheimerove bolesti10 i ostalih promjena u živčanom tkivu,14 kod nefrotoksiciteta13 itd. Na sl. 1 prikazan je princip određivanja raspodjele makromolekula pomoću MALDI TOF masene spektrometrije. Nakon rezanja tankog sloja i fiksiranja, tkivu se dodaje određena supstancija (matrix) koja omogućava optimalnu ionizaciju i mobilizaciju makromolekula. Vrijeme letenja (time of flight) je obrnuto proporcionalno vrijednosti kvocijenta fragmentirane mase i (pozitivnog) naboja m/z. Računalo automatski upravlja sveobuhvatnim snimanjem površine (screening) i daje površinsku sliku rasporeda molekule određene m/z vrijednosti. To se vidi i na slici 4 koja daje raspodjelu molekule s m/z vrijednosti od 7.791 u uzorku bubrega miša otrovanog aristolohijskom kiselinom I (AA I). Na slici 4 je prikazan raspored triju različitih molekula u istim uzorcima. Model miša tretiranog s AA I i AA II je izoliran jer postoje opravdani pokazatelji da je kronično trovanje ovom suspstancijom jedan od uzroka endemskog nefritisa (EN). Endemski nefritis je kronično oboljenje bubrega, proširen u endemskim područjima u donjem toku rijeke Dunava. U Hrvatskoj se ova bolest pojavljuje u određenim selima Brodske Posavine zapadno od Slavonskog Broda. Bakterija Helicobacter pylori je uzročnik infekcije želuca, koja dovodi do kroničnoga gastritisa i, godinama nakon infekcije, do karcinoma. Model miša, inficiranog s Helicobacter pylori pokazuje da 15 dana nakon infekcije dolazi do promjene u raspodjeli proteina, i da protein s m/z vrijednosti 9,962 gotovo nestaje s maseno-spekrometrijskog profila. Ovi pokusi su prvi koraci u definiranju molekulskih promjena kod karcinogeneze želuca, definiciji novih biomarkera za otkrivanje rizika i prognozu kod ove zloćudne bolesti. - IMS je tehnika kojom se kombinira histologija i masena spektrometrija MALDI TOF. - IMS trenutačno nalazi primjenu u medicini, za identifikaciju kandidata za biomarkere za maligne i druge bolesti. - Kao tehnika, imaging mass spectrometry ima velike perspektive za primjenu u agrikulturi, prehrambenoj tehnologiji i biotehnologiji i to za kontrolu kvalitete i praćenja promjena u biljnim, životinjskim tkivima i mikrobnim stanicama tijekom procesa proizvodnje

Cardiotoxicity of fire gases

Prikazani su direktni i indirektni uzroci hipoksije miokarda u požarima. Među prvima su zapreke u opskrbi kisikom, tj. hipoksija u samoj atmosferi požara i karboksihemoglobinemija, a među drugima su zapreke u korištenju kisika, tj. .teško fizičko i psihofizičko opterećenje, karboksimioglobin u miokardu i inhibicija citokromoksidaze cijanovodikom. Kao dodatna opasnost za miokard navedeni su klorirani ugljikovodici (gašenje) i njihovi pirolitički produkti (fozgen). Opširnije je opisana kardiotoksičnost ugljik-monoksida s posebnim osvrtom na Haldaneov učinak i na ponavljane ekspozicije (vatrogasci, pušači, vozači u gustom prometu). Spomenuto je i djelovanje ugljik-monoksida na agregaciju trombocita kao i djelovanje na ubrzanje ateroskleroze. Zbog čestog izgaranja plastlke što sadrži dušika (poliuretani, poliaikrilonitrili, poliamidi .itd.) suvremeni požari proizvode i cijanovodik, pa je opisano i njegovo djelovanje na miokard. Kardiotoksičnost halogeniranih ugljikovodika, proučavana prethodno i vlastitim radovima, posebno je važna za vatrogasce zbog upotrebe halona za gašenje požara. Kod incineracija (smeća) može se u atmosferi pojaviti i tetraklordibenzodioksin (TCDD).Direct and indirect causes of myocardial hypoxia in fires are described. Among the former are the defects in oxygen supply and access i.e. hypoxia in the fire atmosphere and carboxyhaemoglobinaemia, while among the latter are the defects in oxygen disposal and use due to heavy physical and psychophysical efforts, the presence of carboxymyoglobin in the heart muscle and the inhibition of cytochrome oxydase by cyanides. As an additional hazard to the heart muscle chlorinated hydrocarbons (fire extinguishers) or their products (phosgene) should also be considered. The cardiotoxicity of carbon monoxide is presented in detail with special regard to the Haldane effect and repeated exposures (firemen, smokers, drivers of motor vehicles in dense traffic). A possible thrombocyte aggregation effect of carbon monoxide as well as its possible role in the long-term development of atherosclerosis are also dealt with. Because of the frequency of fires involving nitrogen-containing polymers such as polyurethanes, polyacrilonitriles and polyarnides hydrogen cyanide may be produced and its toxic cardiac action should be taken into consideration. The cardiotoxicrty of halogenated hydrocarbons investigated earlier, is outlined is being .important for firemen using halones extinguishers. The appearance of tetrachlorodibenzodioxin (TCDD) in incineration of garbage is also mentioned