Electronic Content in Education – “Media Culture” With(out) Media?

“Media culture” is a course intended for the students of Information Sciences. It includes two different types of knowledge – knowledge of the subject itself and knowledge of one's personal experience with media. The 21st century is changing the learning process in its essence. The traditional classroom teaching is now replaced by the new way of learning - which means developing competences and collecting information and knowledge concerning current problems. This kind of learning is more likely actualization of knowledge from different data bases, than learning for future, or collecting knowledge for possible cognitive challenges. This way the teachers may become some kind of guides and mentors along the learning path. The paper illustrates our way of combining those two types of knowledge. We present the results of our recent research about the use of electronic content in media learning today

Characteristics and selection of cultures of photosynthetic purple non-sulphur bacteria as a potential 5-aminolevulinic acid producers

Wild strains of purple non-sulphur bacteria: Rhodospirillum rubrum B-6505, Rhodopseudomonas palustris B-6506, Rhodobacter capsulatus B-6508 and Rhodobacter spheroides B-6509 were studied as 5-ALA (5 aminolevulinic acid) producers. Selected strains were subjected to mutagenesis with N-methyl-N-nitro-N-nitrosoguanidine to obtain a strain with high 5-ALA producing capacity. After mutagenesis 19 stable mutant strains were selected from Rhodobacter capsulatus B-6508 and Rhodobacter sphaeroides B-6509. On the basis of obtained results, mutant strain of Rhodobacter capsulatus B-6508 has shown the highest potential for 5-ALA production. The most favorable conditions for growth and 5-ALA production by mutant strain R. capsulatus B-6508 were observed in media composed of glutamate and malate, light at 2000 Lux, microaerophilic conditions and temperature of 28 °C. In these conditions, the highest 5-ALA concentration (179 mg/L) was detected together with the highest bacterial physiological activity. The prolongation of mutant strain R. capsulatus B-6508 cultivation time after glycine, succinate and levulinic acid addition is related to the reduction of 5-ALA concentrations (e.g. 124.5 mg/L after 48 h and 89.5 mg/L after 72 hours). In the light/aerobic conditions R. capsulatus B-6508 produced only 58.1 mg/L of 5 ALA. Furthermore, in dark conditions even lower biomass and 5-ALA concentrations were observed during R. capsulatus B-6508 cultivation

Characteristics and selection of cultures of photosynthetic purple non-sulphur bacteria as a potential 5-aminolevulinic acid producers

Wild strains of purple non-sulphur bacteria: Rhodospirillum rubrum B-6505, Rhodopseudomonas palustris B-6506, Rhodobacter capsulatus B-6508 and Rhodobacter spheroides B-6509 were studied as 5-ALA (5 aminolevulinic acid) producers. Selected strains were subjected to mutagenesis with N-methyl-N-nitro-N-nitrosoguanidine to obtain a strain with high 5-ALA producing capacity. After mutagenesis 19 stable mutant strains were selected from Rhodobacter capsulatus B-6508 and Rhodobacter sphaeroides B-6509. On the basis of obtained results, mutant strain of Rhodobacter capsulatus B-6508 has shown the highest potential for 5-ALA production. The most favorable conditions for growth and 5-ALA production by mutant strain R. capsulatus B-6508 were observed in media composed of glutamate and malate, light at 2000 Lux, microaerophilic conditions and temperature of 28 °C. In these conditions, the highest 5-ALA concentration (179 mg/L) was detected together with the highest bacterial physiological activity. The prolongation of mutant strain R. capsulatus B-6508 cultivation time after glycine, succinate and levulinic acid addition is related to the reduction of 5-ALA concentrations (e.g. 124.5 mg/L after 48 h and 89.5 mg/L after 72 hours). In the light/aerobic conditions R. capsulatus B-6508 produced only 58.1 mg/L of 5 ALA. Furthermore, in dark conditions even lower biomass and 5-ALA concentrations were observed during R. capsulatus B-6508 cultivation

Whey Lactose as a Raw Material for Microbial Production of Biodegradable Polyesters

Fossil fuel technologie

Comparison Between Different Cultivation Techniques for Bioethanol Production from Raw Sugar Beet Juice

U ovom istraživanju proučavana je proizvodnja bioetanola na svježem soku šećerne repe s pomoću kvasca Saccharomyces cerevisiae. Za vođenje procesa proizvodnje bioetanola primjenjene su ove tehnike: šaržni proces, šaržni proces s pritokom supstrata i polukontinuirani proces. Tijekom šaržnog procesa proizvodnje bioetanola stupanj konverzije supstrata u produkt (YP/S) je iznosio 0,375 g/g, učinkovitost bioprocesa (E) 69.70 %, te produktivnost (Pr) procesa 0,53 g/Lh. U šaržnom procesu s pritokom supstrata dobivene su ove vrijednosti pokazatelja uspješnosti bioprocesa: YP/S = 0,502 g/g, E = 93,40 % i Pr = 0,50 g/Lh. Nadalje, tijekom polukontinuirane proizvodnje bioetanola pokazatelji uspješnosti bioprocesa su imali ove vrijednosti: YP/S = 0,360 g/g, E = 66,91 % i Pr = 0,66 g/Lh. Na osnovi prethodno prikazanih rezultata jasno je da šaržni proces s pritokom supstrata i polukontinuirani proces imaju značajno veći potencijal za primjenu u industrijskoj proizvodnji bioetanola iako je potrebna daljnja optimizacija polukontinuirane tehnike vođenja bioprocesa.In this investigation, the production of bioethanol on the raw sugar beet juice by Saccharomyces cerevisiae was studied. Following cultivation techniques for bioethanol productions were used: batch, fed batch and repeated batch. In batch process substrate conversion coefficient (YP/S) was 0,375 g/g, bioprocess effi eciency (E) 69,70 % and productivity (Pr) 0,53 g/Lh, respectively. During fed batch process bioprocess efficiency parameters have following values: YP/S = 0,502 g/g, E = 93,4 % and Pr = 0,50 g/Lh. Furthermore, in repeated batch process bioprocess efficiency parameters have following values: YP/S = 0,360 g/g, E = 66,91 % and Pr = 0,66 g/Lh. On the basis of previously presented results it is clear that fed batch and repeated batch processes have considerably higher potential for use in the industrial bioethanol production although further optimization of repeated batch cultivation techniques has to be performed

Proizvodnja etanola iz različitih međuproizvoda obrade šećerne repe

In this investigation, the production of ethanol from the raw sugar beet juice and raw sugar beet cossettes has been studied. For ethanol production from the raw sugar beet juice, batch and fed-batch cultivation techniques in the stirred tank bioreactor were used, while batch ethanol production from the raw sugar beet cossettes was carried out in horizontal rotating tubular bioreactor (HRTB). In both cases, Saccharomyces cerevisiae was used as a production microorganism. During batch ethanol production from the raw sugar beet juice, ethanol yield was 59.89 g/L and production efficiency 78.8 %, and in fed-batch process the yield was 92.78 g/L and efficiency 93.4 %. At the same time, ethanol production in HRTB from the raw sugar beet cossettes with inoculum of 16.7 % V/m (raw sugar beet cossettes) resulted in the highest ethanol yield of 54.53 g/L and production efficiency of 79.5 %. The obtained results clearly show that both intermediates of sugar beet processing can be successfully used for ethanol production.U ovom je istraživanju proučavan proces proizvodnje etanola iz sirovoga soka i sirovih rezanaca šećerne repe. Tijekom proizvodnje etanola iz sirovoga soka u bioreaktoru s miješalom primijenjeni su ovi načini vođenja bioprocesa: šaržni i šaržni proces s pritokom supstrata. Pri proizvodnji etanola iz sirovih rezanaca u horizontalnom rotirajućem cijevnom bioreaktoru primijenjena je šaržna tehnika vođenja bioprocesa. U oba je ova istraživanja kao radni mikroorganizam upotrijebljen kvasac Saccharomyces cerevisiae. Tijekom šaržnog procesa proizvodnje etanola iz sirovoga soka prinos je etanola iznosio 59,89 g/L, a učinkovitost bioprocesa bila 78,8 %. U šaržnom procesu s pritokom supstrata dobiven je prinos etanola od 92,78 g/L uz učinkovitost bioprocesa od 93,4 %. Istodobno je pri proizvodnji etanola iz sirovih rezanaca šećerne repe u horizontalnom rotirajućem cijevnom bioreaktoru s inokulumom od 16,7 % (V/m) dobiven najveći prinos etanola od 54,53 g/L uz učinkovitost bioprocesa od 79,5 %. Rezultati istraživanja jasno pokazuju da se oba međuproizvoda obrade šećerne repe mogu uspješno primijeniti u proizvodnji etanola

Ethanol production from different intermediates of sugar beet processing

In this investigation, the production of ethanol from the raw sugar beet juice and raw sugar beet cossettes has been studied. For ethanol production from the raw sugar beet juice, batch and fed-batch cultivation techniques in the stirred tank bioreactor were used, while batch ethanol production from the raw sugar beet cossettes was carried out in horizontal rotating tubular bioreactor (HRTB). In both cases, Saccharomyces cerevisiae was used as a production microorganism. During batch ethanol production from the raw sugar beet juice, ethanol yield was 59.89 g/L and production efficiency 78.8 %, and in fed-batch process the yield was 92.78 g/L and efficiency 93.4 %. At the same time, ethanol production in HRTB from the raw sugar beet cossettes with inoculum of 16.7 % V/m (raw sugar beet cossettes) resulted in the highest ethanol yield of 54.53 g/L and production efficiency of 79.5 %. The obtained results clearly show that both intermediates of sugar beet processing can be successfully used for ethanol production

Counteraction of perforated cecum lesions in rats: effects of pentadecapeptide BPC 157, L-NAME and L-arginine

AIM: To study the counteraction of perforated cecum lesion using BPC 157 and nitric oxide (NO) system agents. ----- METHODS: Alongside with the agents' application (after 1 min, medication (/kg, 10 mL/2 min bath/rat) includes: BPC 157 (10 μg), L-NAME (5 mg), L-arginine (100mg) alone or combined, and saline baths (controls)) on the rat perforate cecum injury, we continuously assessed the gross reappearance of the vessels (USB microcamera) quickly propagating toward the defect at the cecum surface, defect contraction, bleeding attenuation, MDA- and NO-levels in cecum tissue at 15 min, and severity of cecum lesions and adhesions at 1 and 7 d. ----- RESULTS: Post-injury, during/after a saline bath, the number of vessels was significantly reduced, the defect was slightly narrowed, bleeding was significant and MDA-levels increased and NO-levels decreased. BPC 157 bath: the vessel presentation was markedly increased, the defect was noticeably narrowed, the bleeding time was shortened and MDA- and NO-levels remained normal. L-NAME: reduced vessel presentation but not more than the control, did not change defect and shortened bleeding. L-arginine: exhibited less vessel reduction, did not change the defect and prolonged bleeding. In combination, mutual counteraction occurred (L-NAME + L-arginine) or the presentation was similar to that of BPC 157 rats (BPC 157 + L-NAME; BPC 157 + L-arginine; BPC 157 + L-NAME + L-arginine), except the defect did not change. Thereby at day 1 and 7, saline, L-NAME, L-arginine and L-NAME + L-arginine failed (defect was still open and large adhesions present). ----- CONCLUSION: The therapeutic effect was achieved with BPC 157 alone or in combination with L-NAME and L-arginine as it was able to consolidate the stimulating and inhibiting effects of the NO-system towards more effective healing recruiting vessels

Bypassing major venous occlusion and duodenal lesions in rats, and therapy with the stable gastric pentadecapeptide BPC 157, L-NAME and L-arginine

AIM: To investigate whether duodenal lesions induced by major venous occlusions can be attenuated by BPC 157 regardless nitric oxide (NO) system involvement. ----- METHODS: Male Wistar rats underwent superior anterior pancreaticoduodenal vein (SAPDV)-ligation and were treated with a bath at the ligated SAPDV site (BPC 157 10 μg, 10 ng/kg per 1 mL bath/rat; L-NAME 5 mg/kg per 1 mL bath/rat; L-arginine 100 mg/kg per 1 mL bath/rat, alone and/or together; or BPC 157 10 μg/kg instilled into the rat stomach, at 1 min ligation-time). We recorded the vessel presentation (filled/appearance or emptied/disappearance) between the 5 arcade vessels arising from the SAPDV on the ventral duodenum side, the inferior anterior pancreaticoduodenal vein (IAPDV) and superior mesenteric vein (SMV) as bypassing vascular pathway to document the duodenal lesions presentation; increased NO- and oxidative stress [malondialdehyde (MDA)]-levels in duodenum. ----- RESULTS: Unlike the severe course in the SAPDV-ligated controls, after BPC 157 application, the rats exhibited strong attenuation of the mucosal lesions and serosal congestion, improved vessel presentation, increased interconnections, increased branching by more than 60% from the initial value, the IAPDV and SMV were not congested. Interestingly, after 5 min and 30 min of L-NAME and L-arginine treatment alone, decreased mucosal and serosal duodenal lesions were observed; their effect was worsened at 24 h, and no effect on the collateral vessels and branching was seen. Together, L-NAME+L-arginine antagonized each other's response, and thus, there was an NO-related effect. With BPC 157, all SAPDV-ligated rats receiving L-NAME and/or L-arginine appeared similar to the rats treated with BPC 157 alone. Also, BPC 157 in SAPDV-ligated rats normalized levels of NO and MDA, two oxidative stress markers, in duodenal tissues. ----- CONCLUSION: BPC 157, rapidly bypassing occlusion, rescued the original duodenal flow through IAPDV to SMV flow, an effect related to the NO system and reduction of free radical formation