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Phytochemical composition and antioxidant capacity of aqueous extracts of broccoli (Brassica oleracea L. convar. botrytis var. cymosa) seedlings grown at high temperature
No full textKlimatske promjene i povremeni temperaturni ekstremi utječu na razvoj biljaka za opskrbu prehrambene i ostalih industrija koje koriste biljni materijal kao sirovinu. Kako bi preživjele, biljke svoj kemijski sastav prilagođavaju okolišnim uvjetima, što može uzrokovati i promjenu u nutritivnoj vrijednosti. Svojte iz porodice kupusnjača (Brassicaceae) vrlo su zastupljene u prehrani, a sve veću popularnost stječe i tzv. “mikropovrće“ tj. klijanci zbog kratkog vremena uzgoja, manje potrebnog prostora i resursa, te visoke nutritivne vrijednosti. Brokula pripada najzastupljenijim kupusnjačama u ljudskoj prehrani, čija bi nutritivna vrijednost mogla biti ugrožena zbog porasta okolišne temperature. Stoga je cilj ovog diplomskog rada bio istražiti utjecaj simuliranih uvjeta visoke temperature okoliša na udio primarnih i specijaliziranih metabolita, te antioksidacijski kapacitet vodenih ekstrakata klijanaca brokule (Brassica oleracea L. convar. botrytis (L.) Alef. var. cymosa Duch.). Spektrofotometrijski je određen udio ukupnih fenola, flavonoida, flavonola, hidroksicimetnih kiselina, antocijana, glukozinolata, proteina i topivih šećera. Metodom tekućinske kromatografije visoke moći razlučivanja razdvojeni su, identificirani i kvantificirani L-askorbinska, sinapinska i ferulična kiselina, te flavonoidi kempferol i kvercetin. Visoka temperatura uzrokovala je povećanje udjela ukupnih fenola, flavonola i šećera, kao i koncentracije ferulične i sinapinske kiseline, kvercetina i kempferola. S druge strane, udio ukupnih flavonoida i L-askorbinske kiseline je smanjen. Metodom ABTS zabilježeno je povećanje antioksidacijskog potencijala, a metodom DPPH smanjenje.Global warming has become one of the main challenges of modern civilizations. Climate changes and temperature extremes, affect plant production for food and other industries that use them. Plants can adapt to environment by changing phytochemical composition, which could have a significant impact on plant nutritional value. Species from Brassicaceae family are intesely represented in diet and there is also an increase in usage of „microgreens“ because of shorter growth period, resource usage and good nutritional value. As one of main Brassicaceae species present in the human diet, broccoli production could become endagered because of higher temperature environment condition, so the aim of this work was to investigate metabolic response and the impact of high temperature conditions on primary and secondary metabolites, and antioxidant capacity water extract of broccoli seedlings (Brassica oleracea L. convar. botrytis (L.) Alef. var. cymosa Duch.). The content of total phenols, flavonoids, hydroxycinnamic acids, flavonols, soluble sugars and proteins was determined spectrophotometrically. Using a high-performance-liquid-chromatography method, ferulic, sinapic and L-ascorbic acid, kaempferol and quercetin, were separated, identified and quantified. The antioxidant capacity was determined by methods ABTS, DPPH and FRAP. Higher temperature increased ferulic and sinapic acid, quercetin and kaempferol concentration, total phenols, flavonols and sugars. ABTS method showed and increase in antioxidant capacity, whereas the DPPH showed a decrease. The research also showed a decrease in flavonoids and L-ascorbic acid. The ABTS method showed an increase in the antioxidant potential, while DPPH showed a decrease
Analysis and improvement of metal parts manufacturing process
No full textU ovom radu prikazana je analiza i unaprjeđenje procesa proizvodnje metalnih dijelova,
posebice fokusirajući se na prakse unutar tvrtke Metal Product. Cilj je bio razumjeti postojeće
procese, načine identificije područja za potencijalna poboljšanja te prijedloge koraka
optimizacije proizvodnje. U suradnji s timom i kolegama, prikupiljeni su prijedlozi i
identificirane su ključne potrebe za promjenama. Ti prijedlozi poslužili su kao osnova za
temeljitiju analizu i razvoj strategija za unaprjeđenje.
Tijekom rada u Metal Productu, posebna pažnja posvećena je prikupljanju relevantnih
podataka koji će poslužiti kao temelj za ovaj rad. Analizirani su različiti aspekti proizvodnje,
uključujući dizajn proizvodnih ciklusa, implementaciju novih kapaciteta, digitalne sustave
upravljanja, inovacije u procesima recikliranja i smanjenje otpada. Rad je podijeljen u više
poglavlja, gdje svako poglavlje odgovara određenom segmentu unaprjeđenja procesa.
Jasno je da unaprjeđenje procesa zahtijeva sveobuhvatan pristup, koji uključuje: dizajn novog
prostornog rasporeda (Eng. Layout) proizvodnog ciklusa, implementaciju novih proizvodnih
kapaciteta, novi digitalni sustav za upravljanje proizvodnjom, inovacije u procesima
recikliranja, smanjenje nesukladnih proizvoda i otpada, redizajn radnih mjesta, optimizaciju
tokova sirovina i gotovih proizvoda, stvaranje novih procedura proizvodnje, primjenu
proizvodnje bez papira, uvođenje ekološki prihvatljive ambalaže, smanjenje potrošnje maziva
i vode u proizvodnji, analizu disipacije energije, uvođenje brojila energije te nabavu opreme za
automatizaciju i robotizaciju.
Svaki od ovih segmenata detaljno je analiziran s ciljem identificiranja optimalnih rješenja koja
će pridonijeti efikasnosti, ekološkoj održivosti i ekonomičnosti proizvodnje. Pri tome su
korišteni podatci prikupljeni tijekom prakse i rada u tvrtki, kao i znanstvena literatura i studije
slučaja koje su relevantne za temu. Ovaj pristup omogućio je da se pruži teorijski okvir za
unaprjeđenje procesa proizvodnje u Metal Productu te praktično demonstrira kako se
predložene promjene mogu implementirati u stvarnom poslovnom okruženju. Na kraju, sve
stavke su potkrijepljene izračunima ključnih pokazatelja i cjelokupnom analizom podataka o
uskim grlima i uštedi vremena.This paper presents an analysis and improvement of the metal parts production process,
focusing particularly on practices within the Metal Product company. The aim was to
understand existing processes, identify areas for potential improvements, and propose steps for
optimizing production. In collaboration with the team and colleagues, suggestions were
gathered, and key needs for changes were identified. These suggestions served as the basis for
a thorough analysis and development of strategies for improvement.
Throughout the work at Metal Product, special attention was given to gathering relevant data
to serve as the foundation for this paper. Various aspects of production were analyzed, including
the design of production cycles, implementation of new capacities, digital management
systems, innovations in recycling processes, and waste reduction. The paper is divided into
several chapters, each corresponding to a specific segment of process improvement.
It is evident that process improvement requires a comprehensive approach, including the design
of a new spatial layout of the production cycle, implementation of new production capacities,
a new digital production management system, innovations in recycling processes, reduction of
non-compliant products and waste, redesign of workstations, optimization of raw material and
finished product flows, creation of new production procedures, implementation of paperless
production, introduction of environmentally friendly packaging, reduction of lubricant and
water consumption in production, analysis of energy dissipation, introduction of energy meters,
and procurement of automation and robotics equipment.
Each of these segments was analyzed in detail with the aim of identifying optimal solutions that
would contribute to the efficiency, environmental sustainability, and cost-effectiveness of
production. Data collected during internships and work at the company, as well as relevant
scientific literature and case studies, were used for this purpose. This approach allowed for the
provision of a theoretical framework for improving the production processes at Metal Product
and practically demonstrating how the proposed changes can be implemented in a real business
environment. Finally, all items were supported by calculations of key indicators and a
comprehensive analysis of bottleneck data and time savings
Vimentin expression in nefrotoxic epithelial-mesenchymal transition caused by cysplatine in Wistar rat
No full textCisplatina je jedan od najčešćih kemoterapeutika u liječenju solidnih tumora.Vezanje cisplatine za DNA uzrokuje smrt neoplazmi, dok je nefrotoksičnost glavna negativna strana terapije. U štakorskom modelu nefrotoksičnosti cisplatine dolazi do oštećenja ravnog dijela proksimalnog kanalića (PK). Epitelno-mezenhimalna tranzicija (EMT) se očituje jedinstvenim molekulskim i morfološkim promjenama, pri čemu stanice mijenjaju ekspresiju proteina, gube polarnost, diferenciranost i funkciju epitelne barijere. Prethodno uočene promjene citoskeleta aktina i tubulina u epitelnim stanicama PK uz promjenu ekspresije intermedijarnog proteina vimentina ukazale bi da li se u nefrotoksičnosti cisplatine zbiva EMT. Korišteni su arhivski uzorci modela nefrotoksičnosti nakon jednokratne obrade cisplatinom (i.p. u dozi 5 mg/kg) mužjaka štakora soja Wistar. Najizraženiji učinak toksičnosti javlja se 5. dan nakon tretmana, a pratio se i vremenski tijek u kojem EMT nastaje. Praćenje raspodjele vimentina rađeno je imunofluorescencijski na tkivnim rezovima. Prisutnosti vimentina praćena je u homogenatima tkiva bubrega analizom western blot, dok se promjena u ekspresiji glasničke RNA pratila end- point RT-PCR tehnikom. Pojava ekspresije vimentina uočena je kroz vremenski tijek (3. dan) u tkivnim rezovima te je nađena promjena u prisutnosti proteina u homogenatima tkiva 5. dan. Nefrotoksičnost cisplatine još nije u potpunosti razjašnjena, a naši rezultati pokazuju uključenost EMT koja može objasniti gubitak funkcije bubrega i uputiti na mehanizme obrane od sekundarnih tumora i nefrotoksičnosti kod pacijenata tretiranih cisplatinom.In the treatment of solid tumors, one of the most common chemotherapeutic agents is cisplatin. The binding of cisplatin to DNA causes the death of neoplasms, while nephrotoxicity is the main downside of this therapy. In a rat model of cisplatin nephrotoxicity, damage even part of the proximal tubule (PK) occurs. Epithelial-mesenchymal transition (EMT) manifests itself through unique molecular and morphological changes, wherein cells undergo alterations in protein expression, lose polarity, differentiation, and epithelial barrier function. Previously observed cytoskeletal changes in actin and tubulin in PK epithelial cells, along with a change in the expression of intermediate protein vimentin, would indicate whether EMT occurs in cisplatin nephrotoxicity. Archival nephrotoxicity model samples were used after a single treatment with cisplatin (i.p. at a dose of 5 mg/kg) in male Wistar rats. The most pronounced toxicity effect occurs on the 5th day after treatment, during which the time course of EMT was also monitored. Vimentin distribution was observed through immunofluorescence on tissue sections. The presence of vimentin was monitored in the homogenates of kidney tissue by western blot analysis, while changes in the expression of messenger RNA were monitored using endpoint RT-PCR technique. The appearance of vimentin expression was observed over time (day 3) in tissue sections, and a change in the presence of proteins in tissue homogenates was found on day 5. The nephrotoxicity of cisplatin has not yet been fully elucidated, and our results indicate an involvement of EMT that can explain the loss of kidney function, pointing to defense mechanisms against secondary tumors and nephrotoxicity in patients treated with cisplatin
Analysis of cor samples and identification of Fusarium genus molds
No full textPlijesni roda Fusarium su najbrojniji rod gljivica koje kontaminiraju kukuruz. Poznat je njihov štetan učinak na zdravlje ljudi i životinja, bilo uzrokovanjem fuzarioze ili akutnim i kroničnim trovanjem mikotoksinima, a temperatura zraka i količina padalina su se pokazale kao vrlo značajni čimbenici o kojima ovisi njihova pojavnost na kukuruzu. Klimatske promjene zbog toga uvelike utječu na kontaminaciju kukuruza i prehrambenih proizvoda dovodeći do porasta koncentracija plijesni na usjevima, većih koncentracija kontaminanata u prehrambenim namirnicama i sve većem riziku za ljudsko zdravlje te smanjenoj isplativosti poljoprivrednih uzgoja.
Mikološka analiza metodom razrjeđenja na hranjivim podlogama (DRBC i MGA) provedena je na 50 uzoraka kukuruza od kojih su 25 iz 2021. godine, a 25 iz 2022. godine. Istraživanje je pokazalo je da su koncentracije plijesni veće na uzorcima iz 2022. godine, za koju je prosječna vrijednost koncentracije na DRBC agaru 7,93 x 105 CFU/g dok je za 2021. srednja vrijednost koncentracije na DRBC agaru 1,32 x 105 CFU/g. Srednja vrijednost koncentracije na MGA agaru je također veća za 2022. godinu. Dobivene srednje vrijednosti su vrlo visoke, a većina uzoraka premašuje dozvoljene maksimalne koncentracije koje smiju biti prisutne u hrani.
Na svim uzorcima je došlo do porasta plijesni roda Fusarium, što pokazuje na dominaciju ovog roda kao kontaminanta kukuruza. Na DRBC agaru plijesni roda Penicillium su izrasle na 96% uzoraka, a plijesni roda Aspergillus na njih 72% što ih čini sljedećima po zastupljenosti. Od ostalih plijesni pojavljuju se vrste iz roda Cladosporium, Absidia, Trichoderma i Mucor, a na 28% uzoraka je uočen porast kvasaca. Svi uzorci s kvascima poraslih na DRBC agaru su iz 2022. godine. Na MGA agaru osim fuzarija je također došlo do porasta kvasaca na nekim uzorcima, od kojih je 84% također iz 2022. godine.
Izolacijom i identifikacijom plijesni roda Fusarium primjenom molekularne metode tj. sekvenciranjem genske regije ITS pokazano je da se u većini uzoraka radi o vrsti F. napiforme i/ili F. verticilloides dok je za samo 6% uzoraka identificirana vrsta F. fujikuroi i/ili F. proliferatum. Sve identificirane vrste pripadaju F. fujikuroi kompleksu vrsta. Genska regija ITS pokazala se nedovoljno specifična za razlučivanje srodnih vrsta unutar fuzarijskih kompleksa. Za razlučivanje vrsta unutar pojedinih fuzarijskih kompleksa potrebno je primijeniti više genskih markera kao što su tef1 i rpb2. Visoka učestalost i dominacija vrsta iz kompleksa F. fujikuroi u uzorcima kukuruza može predstavljati opasnost za zdravlje ljudi jer se radi o uzročnicima mikoza kao i o poznatim proizvođačima mikotoksina, poglavito iz skupine fumonizina.Molds of the genus Fusarium are the most prevalent fungi contaminating corn. Their harmful effects on human and animal health are well-documented, either through causing fusariosis or through acute and chronic poisoning by mycotoxins. Air temperature and precipitation levels have been identified as significant factors influencing their occurrence in corn. Consequently, climate change greatly impacts the contamination of corn and food products, leading to increased concentrations of molds in crops, higher contaminant levels in food products, an elevated risk to human health, and reduced profitability in agricultural production.
Mycological analysis using the dilution method on nutrient media (DRBC and MGA) was conducted on 50 corn samples, 25 from 2021 and 25 from 2022. The study revealed that mold concentrations were higher in the 2022 samples, with an average concentration value on DRBC agar of 7.93 x 10⁵ CFU/g, compared to an average concentration value on DRBC agar of 1.32 x 10⁵ CFU/g for 2021. The average concentration value on MGA agar was also higher for 2022. The obtained average values are very high, with most samples exceeding the maximum allowable concentrations permitted in food.
All samples showed an increase in molds of the genus Fusarium, and in the majority of samples, they were the dominant genera. On DRBC agar, molds of the genus Penicillium grew on 96% of samples, and molds of the genus Aspergillus on 72%, making them the next most prevalent. Other molds present included species from the genera Cladosporium, Absidia, Trichoderma, and Mucor, with 28% of the samples showing yeast growth. All samples with yeast growth on DRBC agar were from 2022. On MGA agar, in addition to Fusarium, yeast growth was also observed on some samples, 84% of which were from 2022.
Isolation and identification of molds of the genus Fusarium using molecular methods, specifically sequencing of the ITS gene region, demonstrated that most samples contained the species F. napiforme and/or F. verticillioides, while only 6% of the isolates were identified as F. fujikuroi and/or F. proliferatum. All identified species belong to the F. fujikuroi species complex. The ITS gene region proved to be insufficiently specific for distinguishing closely related species within the Fusarium complexes. To differentiate species within specific Fusarium complexes, the application of multiple genetic markers, such as tef1α and rpb2, is required. The high prevalence and dominance of species from the F. fujikuroi complex in corn samples may pose a risk to human health, as they are known pathogens causing mycoses and are recognized producers of mycotoxins, particularly fumonisins
Strukturna i funkcionalna karakterizacija proteinskog kompleksa hijauronidaze
No full textThe extracellular matrix (ECM) is a complex network of macromolecules that play essential structural and functional roles in tissue organization and the regulation of cellular processes. It undergoes continuous remodeling, primarily mediated by matrix metalloproteinases (MMPs), serine proteases (e.g., human neutrophil elastase, HNE), and hyaluronidases (Hyal). However, these enzymes also contribute to pathological tissue remodeling, leading to conditions such as inflammation, tumor progression, and metastasis. Understanding their molecular characteristics and detailed mechanisms, and developing potential inhibitors is a significant challenge. Despite growing interest, there are only a few studies detailing their protein structures, spatial conformations, oligomerization, physicochemical properties (e.g., the exact pI value for Hyal), or the relationship between their catalytic activity and preparation/analysis conditions. Additionally, the literature lacks information regarding the quality or purity of samples used in catalytic and affinity assays, and the impact of sample quality on in vitro results. This internship project utilizes highly complementary analytical tools. Quality control by UHPLC-ESI-QTOF MS with online desalting and MALDI-TOF MS confirmed the good quality of HNE, MMP-1, and Hyal2 preparations but revealed that BTH is surprisingly impure. Proteomics assays even detected the presence of BSA in BTH samples. Native Liquid MALDI successfully characterized the oligomerization of HNE, MMP-1, and Hyal2. Results indicated that HNE does not form oligomers, MMP-1 forms dimers, and Hyal2 forms tetramers. Furthermore, a significant influence of a crowding agent (dextran 476 kDa) used to mimic the ECM on the inhibition of BTH by both natural and synthetic compounds was demonstrated by CE-UV catalytic assays and by MST affinity tests. This finding underscores the importance of studying proteins under conditions that closely resemble physiological environments. The innovative information collected during this internship will significantly advance studies on ECM targets
Screening of N-acetylneuraminic acid synthase analogues on unnatural substrates
No full textSijalinske kiseline mogu posredovati ili modulirati u širokom spektru fizioloških i patoloških procesa zbog svoje sveprisutne distribucije i strateške lokacije. U posljednjem desetljeću postignut je značajan napredak u proučavanju glikana na ljudskim stanicama, kao i njihove uloge u interakcijama među stanicama. Ugljikohidrati igraju mnogobrojne uloge u različitim organizmima, uključujući razvoj, signalizaciju, interakcije između domaćina i parazita te imunološku funkciju. Iako je provedeno mnogo istraživanja, biologija sijalinske kiseline je još uvijek rastuće područje velikog potencijala čije su primjene tek započele. U ovom radu provedena je kondenzacijska reakcija šećera (L-arabinoza, D-galaktoza, D-liksoza,
D-(+)-manoza) i fosfoenolpiruvata uz prisutnost metalnog kofaktora Co2+. Reakcije su katalizirane analozima sintaze N-acetinneuraminske kiseline (PNH2, PNH5), umjetno dobiveni na temelju sličnosti sa sintazom neuraminske kiseline iz bakterije Neisseria meningitidis. Produkt reakcija su različite sijalinske kiseline. Provedena su ispitivanja s ekstraktom stanica te s pročišćenim enzimom radi potvrde aktivnosti enzima i nastajanja analognih produkata sijalinske kiseline. Uočena je najveća kompatibilnost enzima PNH5 s testiranim šećerima.Sialic acids can mediate or modulate a wide range of physiological and pathological processes due to their omnipresent distribution and strategic location. In the past decade, significant progress has been made in the study of glycans on human cells, as well as their role in cell-cell interactions. Carbohydrates play numerous roles in various organisms, including development, signaling, host-parasite interactions, and immune function. Although much research has been conducted, sialic acid biology is still an emerging field with great potential, while its applications are just beginning. In this study, a condensation reaction of sugars (L-arabinose, D-galactose, D-lyxose, D-(+)-mannose) and phosphoenolpyruvate in the presence of the metal cofactor Co2+. The reactions were catalyzed by analogs of
N-acetylneuraminic acid synthase (PNH2, PNH5), which were artificially derived based on their similarity to the neuraminic acid synthase from the bacterium Neisseria meningitidis.
The product of the reactions are different sialic acids. Assays were conducted on both
cell-free extracts and purified enzyme to confirm the enzyme activity and the formation of sialic acid analogs. The highest compatibility of the enzyme PNH5 with the tested sugars was observed
Determination of heavy metal content in cocoa samples using TXRF-W, TXRF-Mo and EDXRF techniques
No full textPlod stabla kakaovca jest zrno kakaa koje je ključni sastojak u proizvodnji kakao praha i čokolade. Zbog
velike zastupljenosti u ljudskoj prehrani, nužno je poznavanje sastava kakaa kako bi se osigurala kvaliteta i
sigurnost samih proizvoda. Glavni cilj ovog rada jest odrediti elementni sastav kakaa te usporediti rezultate
dobivene različitim analitičkim tehnikama (TXRF-W, TXRF-Mo, EDXRF). Uzorci su pripremljeni
mikrovalnom digestijom te u obliku peleta te je određeno prisustvo sljedećih elemenata: željezo, bakar,
cink, rubidij, stroncij, mangan, nikal i krom. Priprema uzorka u obliku peleta jeftinija je, manje zahtjevna i
ekološki prihvatljivija u odnosu na mikrovalnu digestiju. Analizom je utvrđeno da se rezultati dobiveni
različitim analitičkim tehnikama podudaraju (posebice između TXRF-Mo i EDXRF). Sve su se tehnike
pokazale kao vrlo korisne budući da omogućavaju identifikaciju i kvantifikaciju vrlo niskih koncentracija
elemenata prisutnih u uzorcima kakaa, s naglaskom na TXRF-Mo tehniku koja se pokazala kao
najosjetljivija.The fruit of the cocoa tree is the cocoa bean which is a key ingredient in the production of cocoa powder
and chocolate. Since cocoa is widely used in the human diet, it is necessary to know the composition of
cocoa in order to ensure quality and safety of the products themselves. The main goal of this work is to
determine the elemental composition of cocoa and to compare the results obtained by different analytical
techniques (TXRF-W, TXRF-Mo, EDXRF). The samples were prepared by microwave digestion and in the
form of pellets and the presence of the following elements was determined: iron, copper, zinc, rubidium,
strontium, manganese, nickel and chromium. Sample preparation in the form of pellets is less-expensive,
simpler and more environmentally friendly than microwave digestion. The analysis showed that the results
obtained with the different analytical techniques were consistent (especially between TXRF-Mo and
EDXRF). All techniques have proven to be very effective, as they allow the identification and
quantification of very low concentrations of the elements present in cocoa samples, with the TXRF-Mo
technique which proving to be the most sensitive
Comparison of the effects of different program intesities on the development of children with autism
No full textDjeca s autizmom imaju teškoće i različitosti na području socijalne komunikacije te na području ponašanja, interesa i aktivnosti. Kako bi dobile potrebnu podršku, obitelji se uključuju u različite programe. Još uvijek nije u potpunosti jasno koji intenzitet podrške je optimalan za usvajanje vještina kod djece s autizmom. Još važnije od samog intenziteta je i vrsta programa u koji su obitelji uključene – jesu li ti programi dokazani kao učinkoviti.
Svrha ovog istraživanja bila je saznati hoće li, u kojoj mjeri i na koji način sveobuhvatnija podrška dovesti do usvajanja više vještina kod djece s autizmom u ranoj intervenciji. Cilj je prikazati utjecaj podrške različitog intenziteta i načina pružanja podrške na razvoj vještina kod djece s autizmom: individualno pružanje podrške u usporedbi sa sveobuhvatnim pružanjem podrške koje je uključivalo intenzivni edukacijsko rehabilitacijski program (10 sati tjedno), individualno pružanje podrške (jednom do dva puta tjedno po 60 minuta), grupe podrške za roditelje te edukacije za roditelje, odgojitelje i stručnjake. Korišteni su i analizirani podaci prikupljeni u okviru redovnog rada ustanove, u dosjeima petero dječaka u dobi od 3 do 5 godina. Analiza i usporedba rezultata inicijalnog i finalnog mjerenja VB-MAPP mjernim instrumentom pokazuju vidljiv napredak djece tijekom uključenosti u individualno pružanja podrške, kao i tijekom sveobuhvatnog pružanja podrške, s time da je kod četvero djece uočen veći broj usvojenih vještina tijekom uključenosti u sveobuhvatno pružanje podrške u odnosu na broj usvojenih vještina tijekom individualnog pružanja podrške. Kod jednog od dječaka kod kojeg je individualno pružanje podrške trajalo 6 mjeseci dulje nego sveobuhvatno broj usvojenih vještina u toj razdoblju bio je veći.Children with autism have difficulties and differences in the field of social communication, behavior, interests and activities. Families often seek various forms of support to address their needs. However, the optimal intensity and type of support for enhancing skill acquisition in children with autism remain uncertain. This study aimed to investigate the effects of comprehensive support interventions on skill development in young children with autism. Specifically, we explored the impact of different intensities and modalities of support, including individualized support and a comprehensive program involving intensive educational rehabilitation (10 hours per week), individual sessions (one or two sessions per week lasting 60 minutes each), parent support groups, and educational sessions for parents, caregivers, and professionals. Data from the records of five boys aged 3 to 5 years were collected and analyzed. Analysis of pre- and post-intervention results using the VB-MAPP measurement tool revealed significant progress in children's skill acquisition during both individualized and comprehensive support interventions. Importantly, four children demonstrated a greater increase in acquired skills during comprehensive support compared to individualized support, with one child exhibiting more pronounced improvement after prolonged individualized support lasting over a year
Contribution of emotional regulation, family factors and identity determinants to clarification of the self-aggressive behavior of adolescents
No full textAutoagresivno ponašanje adolescenata predstavlja ozbiljan globalni problem te je povezano sa širokim područjem psihopatologije. Izravno autogresivno ponašanje dijeli se na nesuicidalno samoozljeđivanje (NSSO) i suicidalno ponašanje (koje uključuje ideje, nakane i pokušaje). Cilj ovog istraživanja bio je ispitati ulogu emocionalne regulacije, razvoja identiteta i obiteljskih čimbenika u autoagresivnom ponašanju kod adolescenata s problemima mentalnog zdravlja. U studiju je uključeno 100 sudionika, u dobi od 12 do 17 godina, 39 dječaka i 61 djevojčica. Sudionici su bili prvi put pregledani u Psihijatrijskoj bolnici za djecu i mladež od strane dječjeg psihijatra te im je postavljena dijagnoza mentalnog poremećaja. Pola sudionika je iskazivalo autoagresivno ponašanje, dok druga polovica nije. Podaci su prikupljani nakon psihijatrijske procjene, te dobivene suglasnosti od djece i roditelja, metodom papir-olovka. Adolescenti su ispunjavali samoocjenske upitnike, a roditelji sociodemografski upitnik. U istraživanju su korišteni instrumenti: Izvješće za mlade od 11 do 18 godina (YSR; Achenbach i Rescorola, 2001), Upitnik procjene razvoja identiteta u adolescenciji (AIDA; Goth i sur., 2012a), Upitnik procjene obitelji (FAD; Epstein i sur., 1983), Upitnik poteškoća emocionalne regulacije (DERS; Gratz i Roemer, 2004), Inventar namjernog samoozljeđivanja (DSHI; Gratz, 2001) te sociodemografski upitnik. Obrada podataka uključivala je deskriptivnu analizu, hijerarhijsku regresijsku analizu s testiranjem medijacijskih efekata te testiranje pristajanja modela pomoću SEM analize. Glavni nalazi ukazuju na značajan doprinos obiteljskog funkcioniranja i diskontinuiteta identiteta u objašnjenju pojave autoagresivnog ponašanja. Adolescenti koji su izvještavali o lošijem obiteljskom funkcioniranju, kao i oni s izraženijim diskontinuitetom identiteta iskazali su i više autoagresivnog ponašanja. Emocionalna regulacija se pokazala značajnim parcijalnim medijatorom u vezama obiteljskog funkcioniranja te diskontinuiteta identiteta i autoagresivnog ponašanja. U modelu u kojem su uključena sva tri čimbenika, funkcioniranje obitelji ostvaruje samo značajan direktni efekt na autoagresivno ponašanje, dok emocionalna regulacija postaje potpuni medijator u vezi između diskontinuiteta identiteta i autoagresivnog ponašanja. Teorijski model ima dobro pristajanje s podacima. Doprinos istraživanja se prvenstveno odnosi na razumijevanje korelata autoagresivnog ponašanja u sveobuhvatnom modelu kakav do sad nije ispitan.Introduction
Autoaggressive behavior in adolescence is a serious global problem and is associated with a wide range of psychopathological problems. Direct autoggressive behavior it can be divided into non-suicidal self-harm (NSSI) and suicidal behavior (which includes suicidal ideas, plans and attempts). Recent studies show that the range of global NSSI prevalence, among adolescents, goes up to 27% (Xiao et al., 2022), suicidal ideas up to 23%, and suicidal attempts up to 16% (Van Meter et al., 2023). These numbers indicate the seriousness of the problem. The most common risk factors for autoaggressive behavior include sociodemographic factors, family factors, history of abuse, and psychological/psychiatric factors. Some authors found the correlation between the emotional dysregulation and autoaggressive behavior among adolescents (Kranzler et al., 2016). In that context, autoaggressive behavior can serve them to express, validate or regulate their dysphoric emotions such as stress, anger, depression, or dissociation (Nixon et al.,2002). Family is listed as one of the most important predictors of autoaggressive behavior (Cassels et al., 2018), but also as an important factor in development of emotional regulation (Morris et al., 2007). Besides family functioning and emotional regulation, researches have found that identity development also has an important role in displaying autoaggressive behavior in a way that adolescents with more conflicted identity have higher tendency towards NSSI (Toukhy et al., 2022). However, most studies explored these correlations with simple models, and more comprehensive models, that include more than one or two factors, are missing. For that reason, this research seeks to cover all these relevant factors, and investigate their complex correlations with autoaggressive behavior.
Aim and Research Problems
The aim of this research was to investigate the role of emotional regulation, the development of identity, and family factors in autoaggressive behavior among adolescents with mental health problems.
The research problems were: to determine the type of mental health difficulties in examined adolescents as well as presence of autoaggressive behavior; to determine the relative contribution of the family functioning, family communication, and family affective reactions in the explanation of autoaggressive behavior among adolescents; to determine relative contribution of identity development in adolescents with and without autoaggressive behavior;
to explore the mediation effect of emotional regulation in the relationship between family factors and autoaggressive behavior as well as in the relationship between identity development and autoaggressive behavior.
Method
100 participants were included in this study. Participants were 12 to 17 years old, 39 of them were boys, and 61 were girls. The participants were examined for the first time at the Psychiatric Hospital for Children and Youth by a child psychiatrist and were diagnosed with a mental disorder. Half of the participants displayed autoaggressive behavior, while the other half did not. The data were collected after a psychiatric assessment, and consent was obtained from the children and parents, using the paper-pencil method. Adolescents filled out self-assessment questionnaires, and parents a sociodemographic questionnaire. The following instruments were used in the survey: Youth Self Report (YSR; Achenbach and Rescorola, 2001), Assessment of Identity Development in Adolescence (AIDA; Goth et al., 2012a), Family Assessment Device (FAD; Epstein et al., 1983), Difficulties in Emotion Regulation Scale (DERS; Gratz and Roemer, 2004), Deliberate Self Harm Inventory (DSHI; Gratz, 2001) and a sociodemographic questionnaire. The adolescents filled up self report scales and parents answered the sociodemographic questionnaire. Data analyses included descriptive statistics, hierarchical regression analysis, with testing the mediation effects, and structural equation modelling (SEM).
Results
Most of participants in this research were diagnosed with emotional disorders with the beginning specifically in childhood and other emotional disorders in childhood. Participants who displayed autoaggressive behavior had higher anxiety and depression scores, displayed more withdrawal symptoms, more physical and social disabilities, thinking problems, attention problems, tendency to violate rules, and more aggressive behavior. Furthermore, the findings indicate a significant contribution of family functioning and discontinuity of identity in explaining the appearance of autoaggressive behavior. Adolescents who reported poor family functioning, as well as those with a higher score on discontinuity of identity, have expressed more autoaggressive behavior. Emotional regulation has proven to be a significant partial mediator in the relationships between family functioning and autoaggressive behavior as well as discontinuity of identity and autoaggressive behavior. In a structural model, the family functioning had a significant direct effect on autoaggressive behavior, but was not mediated by
emotional regulation. However, relationship between discontinuity of identity and autoaggressive behavior was fully mediated by emotional regulation. The theoretical model had a good fit with observed data.
Conclusion
This study has shown that participants, who are prone to autoaggressive behavior often express multiple levels of other psychological difficulties. A significant role of family functioning and discontinuity of identity in predicting autoaggressive behavior, as well as the mediation effect of emotional regulation in these relationships, was confirmed. Such findings indicate an important role of family functioning, discontinuity of identity and emotional regulation in the development of autoaggressive behavior among adolescents, and provide an important scientific contribution though better understanding of the complex relationships between these factors. In addition, the findings also provide a valuable practical contribution, creating the foundation for the development of more efficient prevention programs for autoaggressive behavior among adolescents
Design of a lower leg prosthesis improvement
No full textPotkoljenične proteze, koje zamjenjuju donji dio noge ispod koljena, omogućuju korisnicima ponovno stjecanje mobilnosti i neovisnosti. Kroz povijest, razvoj potkoljeničnih proteza prošao je kroz različite faze inovacija, no i dalje postoji značajan prostor za unapređenje, posebno u području prilagodbe karakteristika proteze samom korisniku. Kako je tema ovog diplomskog rada Konstrukcijsko poboljšanje potkoljenične proteze rad se sastoji od teorijskog dijela, dijela konstrukcijske poboljšanja i praktičnog dijela. U samom teorijskom dijelu su obrađene teme koje su potrebne kako bi se stvorila podloga za razumijevanje problema i samim time određivanja konstrukcijskih zahtjeva potrebnih za poboljšanje potkoljenične proteze. Kroz teorijski dio ovog rada obrađene su teme podjele proteza s obzirom na njihovu upotrebu i vrstu amputacije. Također, u samom je korištena tehnologija 3D printanja, stoga je i opisana aditivna proizvodnja kao efikasni postupak izrade prototipova za testiranje. U dijelu konstrukcijskog poboljšanja je s obzirom na pregled postojećih rješenja na tržištu i definiranja funkcionalnih i konstrukcijskih zahtjeva razvijen koncept koji predstavlja konstrukcijsko poboljšanje potkoljenične proteze. U zadnjem dijelu ovog rada su na osnovu koncepta izrađena tri prototipa korištenjem tehnologije 3D printanja. Prototipovi su nakon toga ocjenjivani kako bi odredili koji je najbolje rješenje. Prema odabranom prototipu se aditivnom proizvodnjom izradila cijela potkoljenična proteza za trčanje. Rezultat ovog rada je izrađena cjenovno prihvatljiva potkoljenična proteza promjenjive krutosti stopala.Transtibial prostheses, which replace the lower part of the leg below the knee, enable users to regain mobility and independence. Throughout history, the development of transtibial prostheses has gone through various phases of innovation, but there remains significant room for improvement, particularly in the area of adapting the prosthesis characteristics to the individual user. As the topic of this thesis is the constructional improvement of transtibial prostheses, the work consists of a theoretical part, a constructional improvement part and a practical part. The theoretical part covers topics necessary to create a foundation for understanding the problem and thus determining the constructional requirements needed for improving the below-knee prosthesis. Through the theoretical section, topics such as the classification of prostheses based on their use and the type of amputation are addressed. Additionally, since 3D printing technology was utilized, additive manufacturing is described as an efficient process for creating prototypes for testing. In the constructional improvement section, based on the review of existing solutions on the market and the definition of functional and constructional requirements, a concept representing the constructional improvement of the below-knee prosthesis was developed. In the final part of this work, three prototypes were created based on the concept using 3D printing technology. The prototypes were then evaluated to determine which one was the best solution. According to the chosen prototype, an entire below-knee running prosthesis was manufactured using additive manufacturing. The result of this work is a cost-effective transtibial prosthesis with adjustable foot stiffness