137 research outputs found
Photocatalysis of organic effluents
PhD ThesisHeterogeneous photocatalytic oxidation is a relatively new technology
for the destruction of toxic organic substances in water and so far has
concentrated on reaction mechanisms and kinetics, but the engineering side
was hardly touched. In this study a detailed investigation for suitable reactor
design has been carried out using three different reactor types.
An annular photoreactor was used with two different lamps with
different intensities; low pressure and medium pressure mercury lamps. Two
types of Ti02 powder catalysts Degussa P-25 and Tioxide PCi were used as
slurry solutions and Degussa P-25 was found more photocatalytically active
than the other. Two main organic reactants salicylic acid and 4-chlorophenol
were studied to assess the light intensity effect. Although better reaction rates
were achieved with the higher intensity medium pressure lamp, quantum
yield results showed that low pressure lamp photons were utiised more
effectively.
The falling film reactor (FFR) was used to increase the light intensity
utilisation with the stronger medium pressure lamp and using the same
reactants in slurries catalysts Degussa P-25 gave superior results to those in
annular reactor. Because of the thin film characteristics, FFR provided good
oxygen transfer at the film/air interface. A commercial supported catalyst
system as a fibre glass gauze was also used inside the reactor and was found
as effective as slurry systems.
In order to improve the thin film characteristics and combine these
with an immobiised catalyst, a spinning disc reactor (SDR) with catalyst
coated borosilicate disc was used to degrade aqueous solutions of 4-
chlorophenol and salicylic acid. It was found that the efficiency of the
photocatalyst process was dependent upon the type of UV source used.
Lamps supplying shorter wavelength UV radiation were found to be more
efficient than those whose emissions lay mainly in the near UV region. The
method used to coat the disc of the SDR does not appear to meet its
operational requirements.Istanbul Technical University.
Higher Education Council of Turkey
Inhibiciја оksidаciје lipidа u ulju inćuna pomoću albеdо ekstrakta iz grејpfruta
The effect of grapefruit peel albedo extracts on the oxidation of fish lipids was investigated. Extracted anchovy (Engrailus engrasicolus) oil and grapefruit (Citrus paradisi)albedo extract was used as research material.
The extract of albedo fragments of grapefruit were added into the fish lipid in the concentrations of 0.5, 1.0 and 2.0 mg/g. The fish lipid without extract was regarded as control group. The samples were stored at 25°C and analyses were performed on weekly intervals. The phenolic content and antioxidant activity determined in albedo fragments of grapefruit were 6.61±0.01g GAE/100 g and 0.170±0.014 µM trolox, respectively. Grapefruit peel albedo extract treatments has successful results in suppression of fish lipid oxidation. TBA, para-anisidine, and peroxide values of extract samples were lower than control samples during the storage. The highest UV spectrum values were observed in control samples at the end of the storage period. The highest extract concentration(2.0 mg/g) treatment was more effective than the other concentrations in hinderinglipid oxidation. In conclusion, the extract of grapefruit albedo extracts can be used as a natural antioxidant and the by-products of the peels can be evaluated economically without giving harm to the environment.Ispitan je efеkаt аlbеdo еkstrаkаtа iz kоrе grејpfrutа nа оksidаciјu lipidа ribе. Ekstrahovano ulje inćuna (Еngrаilus еngrаsicоlus) i albеdо ekstrakt iz grејpfruta(Citrus pаrаdisi) korišćeni su kао mаtеriјаl u toku istraživanja.Еkstrаkt аlbеdо frаgmеnаtа grејpfruta su dоdаti lipidimа ribe u kоncеntrаciјаmа оd 0,5, 1,0 i 2,0 mg/g. Lipidi ribe bеz dodatog еkstrаkta korišćeni su kao kоntrоlnа grupа. Uzоrci su čuvаni nа 25°C i аnаlizirani su u nеdеlјnim intеrvаlimа. Vrednosti za sаdržај fеnоlna i аntiоksidаtivnu аktivnоst koje su ustanovljene u albеdо frаgmеntimа grејpfrutа iznosile su 6,61 ± 0.01g GАЕ / 100 g i 0.170 ± 0.014 µМ trоlоksa, rеspеktivnо. Trеtmаni sa аlbеdо еkstrаktima iz kore grејpfruta dali su uspеšnе rеzultаtе u suzbiјаnju оksidаciје lipidа ribе. Tоkоm sklаdištеnjа, ТBА, pаrа-аnizidin i pеrоksidne vrеdnоsti u uzоrcima еkstrаktа bilе su nižе od istih vrednosti u kоntrоlnim uzоrcima. Nајveće vrеdnоsti UV spеktarа su uоčеnе u kоntrоlnim uzоrcimа nа krајu pеriоdа skladištenja. U sprečavanju оksidаciје lipidа nајvеćа kоncеntrаciја ekstrakta (2,0 mg/g) u trеtmаnu bilaje еfikаsniјa оd оstаlih kоncеntrаciја.Kao zаklјučak, albеdо еkstrаkt iz grејpfrutа mоžе da se kоristi kао prirоdni аntiоksidаns, a spоrеdni prоizvоdi koji se dobijaju iz kore mоgu da imaju еkоnоmski značaj bеz ugrožavanja životne sredine
Baby steps to a child-to-child network: A path to empower children for exercising their participation rights
This study focuses on an adult-initiated and child-led research journey that aimed to explore the path to empower children towards exercising their participation rights in different environments of their lives. To this end, a series of multi-stage participation empowerment activities were carried out with 60 children in Istanbul, as guided by the child participation model and ecological systems theory. Findings are narrated through children's voices and illustrate their multifaceted opinions, challenges and demands with respect to how they participate in life. Children's experiences in this research journey suggest that grassroots of a child-to-child participation network is possible via empowerment and capacity building activities
Efektı dodatka transglutamınaze na promene kvalıteta mlevenog mesa dužıčaste pastrmke
The effect of transglutaminase on the quality of fish mince was determined during refrigerated storage. For this purpose, the proportions of 0.2%, 0.5% and 1.0% microbial transglutaminase enzyme (MTGase) was added into trout (Oncorhynchus mykiss) mince meat. The pH value of trout mince decreased at the end of the cold storage and the lowest scores (6.00±0.01) were determined with the samples treated with 0.5% enzyme. The fish mince kept its consumable “good” quality on the 8th day of cold storage depending on total volatile basic nitrogen (TVB-N) values. However, TVB-N values of control samples increased rapidly comparing to the other treatments. The trimethylamine nitrogen (TMA-N) values increased during storage and the highest scores were recorded in control samples at the end of the storage. The addition of MTGase caused no difference on the total free amino acid content among the treatment groups. It was recorded that the progress in total free amino acids was suppressed with the addition of MTGase. The increase in enzyme concentration met successful results in hindering the growth of total psychrophilic bacteria and coliform bacteria and the best results were obtained with the addition of MTGase in the concentration of 1.0%. The increase in the enzyme concentration affected the sensory scores of fish mince positively.Efekat transglutaminaze na kvalitet ribljeg mlevenog mesa ispitan je u toku skladištenja u frižiderima. U ove svrhe, enzim mikrobijalna transglutaminaza (MTGase) u razmeri od 0.2%, 0.5% i 1.0% je dodavana u mleveno meso pastrmke (Oncorhynchus mykiss).
pH vrednost mlevenog mesa pastrmke je opala na kraju skladištenja na hladnom, a najniži skor (6.00±0.01) je određen kod uzoraka koji su tretirani sa 5% enzima. U zavisnosti od vrednosti TVB-N (ukupni isparljivi azot), riblje mleveno meso je održalo svoj kvalitet tako da je moglo da se konzumira osmog dana nakon skladištenja na hladnom. Međutim, TVB-N vrednost kontrolnih uzoraka se povećala mnogo brže u odnosu na druge tretmane. TMA-N (trimetilamin azot) vrednosti su se povećale tokom skladištenja, a najviši skorovi su zabeleženi kod kontrolnih uzoraka na kraju peroda skladištenja. Dodatak MTGaze (mikrobialna transglutaminaza) nije uticala na ukupan sastav slobodnih amino kiselina među tretiranim grupama. Zabeleženo je da je progres ukupnih slobodnih amino kiselina potisnut dodatkom MTG-a. Povećanje koncentracije enzima je pozitivno uticalo na sprečavanje rasta ukupne količine psikrofilnih i koliformnih bakterija i najbolji rezultati dobijeni su dodavanjem MTG-a koncentraciji od 1.0%. Povećanje koncentracije enzima je pozitivno uticalo na senzorna svojstva ribljeg mlevenog mesa
Aspirin-triggered resolvin D1 reduces pneumococcal lung infection and inflammation in a viral and bacterial coinfection pneumonia model
Formyl peptide receptor 2/lipoxin A4 (LXA4) receptor (Fpr2/ALX) co-ordinates the transition from inflammation to resolution during acute infection by binding to distinct ligands including serum amyloid A (SAA) and Resolvin D1 (RvD1). Here, we evaluated the proresolving actions of aspirin-triggered RvD1 (AT-RvD1) in an acute coinfection pneumonia model. Coinfection with Streptococcus pneumoniae and influenza A virus (IAV) markedly increased pneumococcal lung load and neutrophilic inflammation during the resolution phase. Fpr2/ALX transcript levels were increased in the lungs of coinfected mice, and immunohistochemistry identified prominent Fpr2/ALX immunoreactivity in bronchial epithelial cells and macrophages. Levels of circulating and lung SAA were also highly increased in coinfected mice. Therapeutic treatment with exogenous AT-RvD1 during the acute phase of infection (day 4–6 post-pneumococcal inoculation) significantly reduced the pneumococcal load. AT-RvD1 also significantly reduced neutrophil elastase (NE) activity and restored total antimicrobial activity in bronchoalveolar lavage (BAL) fluid (BALF) of coinfected mice. Pneumonia severity, as measured by quantitating parenchymal inflammation or alveolitis was significantly reduced with AT-RvD1 treatment, which also reduced the number of infiltrating lung neutrophils and monocytes/macrophages as assessed by flow cytometry. The reduction in distal lung inflammation in AT-RvD1-treated mice was not associated with a significant reduction in inflammatory and chemokine mediators. In summary, we demonstrate that in the coinfection setting, SAA levels were persistently increased and exogenous AT-RvD1 facilitated more rapid clearance of pneumococci in the lungs, while concurrently reducing the severity of pneumonia by limiting excessive leukocyte chemotaxis from the infected bronchioles to distal areas of the lungs
IL-17A and serum amyloid A are elevated in a cigarette smoke cessation model associated with the persistence of pigmented macrophages, neutrophils and activated NK cells
While global success in cessation advocacy has seen smoking rates fall in many developed countries, persistent lung inflammation in ex-smokers is an increasingly important clinical problem whose mechanistic basis remains poorly understood. In this study, candidate effector mechanisms were assessed in mice exposed to cigarette smoke (CS) for 4 months following cessation from long term CS exposure. BALF neutrophils, CD4+ and CD8+ T cells and lung innate NK cells remained significantly elevated following smoking cessation. Analysis of neutrophil mobilization markers showed a transition from acute mediators (MIP-2α, KC and G-CSF) to sustained drivers of neutrophil and macrophage recruitment and activation (IL-17A and Serum Amyoid A (SAA)). Follicle-like lymphoid aggregates formed with CS exposure and persisted with cessation, where they were in close anatomical proximity to pigmented macrophages, whose number actually increased 3-fold following CS cessation. This was associated with the elastolytic protease, MMP-12 (macrophage metallo-elastase) which remained significantly elevated post-cessation. Both GM-CSF and CSF-1 were significantly increased in the CS cessation group relative to the control group. In conclusion, we show that smoking cessation mediates a transition to accumulation of pigmented macrophages, which may contribute to the expanded macrophage population observed in COPD. These macrophages together with IL-17A, SAA and innate NK cells are identified here as candidate persistence determinants and, we suggest, may represent specific targets for therapies directed towards the amelioration of chronic airway inflammation
Efekti tumbanja na fizičke ı hemıjske odlıke hobotnıce (octopus vulgaris)
Common octopus (Octopus vulgaris) is a cephalopod eaten mainly in Mediterranean, South American and Oriental countries and is typically marketed fresh, frozen and dried salted. Cephalopods in general and octopus in particular have a very firm and tough texture, especially when fresh. This toughness is associated with the collagen structure, content and aggregation in the cephalopod muscles. Collagen in octopus is tenderized mainly by heating, usually in boiling water. The traditional way to overcome octopus toughness has been the repeated “beating” of the freshly caught octopus on the rocks by the sea. This procedure has been adopted by the industry the mechanical “beating” of octopus is performed in specialized tumbling equipment, where octopus is tumbled in water. Tumbling processes are commonly used to disrupt the muscle structure, disintegrate external surfaces of meat pieces and to release myofibrillar proteins. In general, tumbling improves tenderness while NaCl (in low concentrations) helps the extraction of proteins and improves the water-holding capacity of the muscle increasing the tenderness of the final product. Tumbling process has been studied for other meats for tenderization. However there is in limited amount of study on use of tumbling on octopus.
The main objective of this study is to investigate the effects of tumbling process on physicochemical properties of octopus muscle. Octopus (Octopus vulgaris) was obtained from the main fish market of Antalya. They were purchased just after landing and placed in cold storage bag with ice. Tumbling process was carried out using a tumbler specially designed for this study. Tumbling process was performed continuously in 3 different tumbling times (2, 4, 6 h). After tumbling, the samples were analysed. According to results tumbling was effective on physicochemical properties of octopus. Tumbling time affected all parameters. With increase in tumbling time increased in tenderness of octopus muscle. Total soluble protein, total free amino acid and pH values increased with increase of tumbling time. Water holding capacity decreased and cooking loss increased. According to instrumental texture measurements, hardness and shear force values decreased after tumbling process. As a result, tumbling was found as effective method to tenderize of octopus muscle.Hobotnica (Octopus vulgaris) je glavonožac koji se konzumira pretežno na Mediteranu, u Južnoj Africi i Istočnim zemljama sveta. Najčešće se plasira na tržište sveža, zaleđena ili suva usoljena. U načelu, sveži glavonošci, a naročito hobotnica, imaju veoma čvrstu i žilavu strukturu. Ova čvrstina potiče iz strukture i sastava kolagena, i njegovog nakupljanja u mišićima glavonožaca. Kod hobotnice, kolagen se najčešće opušta u vrućoj, najčešće ključaloj vodi. Tradicionalan način ublažavanja čvrstine kod hobotnice bio je ‘mlaćenje’ sveže ulovljene hobotnice o stene pored mora. Industrija je usvojila ovu proceduru, tako da se mehanično ‘mlaćenje’ primenjuje u specijalizovanoj opremi za tumbanje, gde se hobotnica tumba u vodi. Proces tumbanja se često koristi da se poremeti struktura mišića, razgrade spoljne površine komada mesa i otpuste protein iz miofibrila. Tumbanje poboljšava nežniju strukturu hobotnice dok NaCl (u niskim koncentracijama) pomaže izlučivanje proteina i poboljšava kapacitet mišića za zadržavanjem vode i na taj način povećava nežnost krajnjeg proizvoda. Proces tumbanja ispitivan je za omekšavanje drugih vrsta mesa. Međutim, postoji ograničen broj studija koje se bave upotrebom tumbanja na hobotnice.
Osnovni cilj ovog istraživanja jeste da ispita efekte koje process tumbanja ima na fizičkohemijske odlike mišića hobotnice. Hobotnica (Octopus vulgaris) sa glavne pijace ribe u Antaliji. Odmah pošto je dospela na kopno, hobotnica je kupljena i stavljena u hladne kese za skladištenje sa ledom. Proces tumbanja izvršen je korišćenjem mašine za tumbanje koja je posebno dizajnirana za ovu studiju. Proces tumbanja izvršen je u kontinuitetu, sa 3 različite dužine trajanja procesa (2, 4, 6 sati). Posle tumbanja, uzorci su podvrgnuti analizi. Rezultati su pokazali da je tumbanje imalo pozitivan efekat na fizičkohemijske odlike hobotnice. Dužina trajanja tumbanja uticala je na sve parametre. Sa povećanjem trajanje tumbanja, povećavala se i nežnost mišića hobotnice. Ukupna količina rastvorljivog proteina, ukupna količina amino kiselina i pH vrednosti su se povećale sa povećanjem trajanja tumbanja. Kapacitet za zadržavanjem vode se smanjio a gubitak pri kuvanju povećao. Prema merenjima teksture instrumentima, čvrstina i vrednosti poprečne sile su se smanjile posle procesa tumbanja. Zaključeno je da je process tumbanja efikasan metod za opuštanje mišića hobotnice
Multiresidue Method for the Simultaneous Analysis of Antibiotics and Mycotoxins in Feeds by Ultra-High Performance Liquid Chromatography Coupled to Tandem Mass Spectrometry
Residues in animal feeds and foods of animal origin have been important safety issue concerning both human and animal health. A multiresidue method for determination of eight mycotoxins and ten antibiotics was developed and validated in animal feeds by using QuEChERS (quick, easy, cheap, effective, rugged, and safe) extraction followed by UHPLC-MS/MS. Optimisation of UHPLC-MS/MS parameters was performed to achieve good separation and resolution. The method was validated according to the European Commission Decision 2002/657/EC. Matrix matched calibration curves showed good r2 (≥0.995) values, and limit of quantification (LOQ) values varied between 1.2 and 5.2 mg kg1. Average recoveries ranged from 60 to 102% with relative standard deviations of 2.2 and 15.6% for all type of feed samples except for tetracyclines, lincomycin, tylosin, ochratoxin A, and fumonisin (B1 and B2)
Enhanced β-mannanase production from alternative sources by recombinant Aspergillus sojae
Aspirin-triggered resolvin D1 reduces pneumococcal lung infection and inflammation in a viral and bacterial coinfection pneumonia model
Formyl peptide receptor 2/lipoxin A4 (LXA4) receptor (Fpr2/ALX) co-ordinates the transition from inflammation to resolution during acute infection by binding to distinct ligands including serum amyloid A (SAA) and Resolvin D1 (RvD1). Here, we evaluated the proresolving actions of aspirin-triggered RvD1 (AT-RvD1) in an acute coinfection pneumonia model. Coinfection with Streptococcus pneumoniae and influenza A virus (IAV) markedly increased pneumococcal lung load and neutrophilic inflammation during the resolution phase. Fpr2/ALX transcript levels were increased in the lungs of coinfected mice, and immunohistochemistry identified prominent Fpr2/ALX immunoreactivity in bronchial epithelial cells and macrophages. Levels of circulating and lung SAA were also highly increased in coinfected mice. Therapeutic treatment with exogenous AT-RvD1 during the acute phase of infection (day 4–6 post-pneumococcal inoculation) significantly reduced the pneumococcal load. AT-RvD1 also significantly reduced neutrophil elastase (NE) activity and restored total antimicrobial activity in bronchoalveolar lavage (BAL) fluid (BALF) of coinfected mice. Pneumonia severity, as measured by quantitating parenchymal inflammation or alveolitis was significantly reduced with AT-RvD1 treatment, which also reduced the number of infiltrating lung neutrophils and monocytes/macrophages as assessed by flow cytometry. The reduction in distal lung inflammation in AT-RvD1-treated mice was not associated with a significant reduction in inflammatory and chemokine mediators. In summary, we demonstrate that in the coinfection setting, SAA levels were persistently increased and exogenous AT-RvD1 facilitated more rapid clearance of pneumococci in the lungs, while concurrently reducing the severity of pneumonia by limiting excessive leukocyte chemotaxis from the infected bronchioles to distal areas of the lungs
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