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Application of the model of subsequent measurement of long-term tangible assets and their impact on the financial position and success of the business entity
No full textDugotrajna materijalna imovina značajna je stavka u poslovanju svakog poslovnog subjekta. Ona je potrebna svakom poslovnom subjektu za neprekidan nastavak poslovanja, a u većini poslovnih subjekata se uobičajeno javlja u obliku građevinskih objekata, zemljišta, strojeva, opreme, alata, pogonskog inventara, transportne imovine, biološke imovine i slično. Dugotrajna materijalna imovina je imovina čiji je vijek trajanja duži od jedne godine, te se neće utrošiti u jednom proizvodnom ili poslovnom procesu, te se od nje očekuje buduća ekonomska korist. Poslovni subjekti imovinu početno mjere po trošku nabave, dok ju naknadno mjere po jednom od modela naknadnog mjerenja, odnosno ovisno o tome je li riječ o imovini koja se upotrebljava u realizaciji poslovnih aktivnosti (u tom slučaju se imovina mjeri primjenom modela troška ili modela revalorizacije) ili je riječ o ulaganjima u nekretnine (u tom slučaju se imovina mjeri primjenom modela troška ili modela fer vrijednosti). Svaki pojedini model naknadnog mjerenja ima različit utjecaj na financijski položaj i uspješnost poslovnog subjekta.Long-term tangible assets are an important item of every business entity. It is needed by every business entity for uninterrupted business continuity, and in most business entities it usually occurs in the form of buildings, machines, tools, biological assets and similar. A long-term tangible asset is an asset that will be used for more than one year, and future economic benefit is expected from it. Business entities initially measure assets acquisition cost, while they are subsequently measured according to one of the subsequent measurement model, that is, depending on whether the property is used in the implementation of business activities (in this case the property is measured using the cost model or the revaluation model) or whether it is an investment in real estate (in this case the property is measured using the cost model or the fair value model). Each individual model of subsequent measurement has a different impact on the financial position and performance of the business entity
Relationship between the hybrid way of working and employee work engagement
No full textRad od kuće predstavlja klasičan model fleksibilnog radnog aranžmana kreiran sa svrhom da poslodavac svome zaposleniku omogući fleksibilnost i autonomiju u radu te da stekne konkurentsku prednost na tržištu rada. Pojavom pandemije virusa COVID-19 većina poduzeća bila je primorana dinamiku radnog okruženja prilagoditi novim uvjetima. Posljedično, uvode se razni novi oblici fleksibilnog načina rada, među kojima vrijedi istaknuti hibridan način rada – kombinaciju rada od kuće i rada na radnom mjestu. Unatoč izazovima koje donosi rad od kuće, mnogi zaposlenici ne žele se odreći takvog načina rada jer se na taj način smatraju produktivnijima u svom poslu, dostupna im je veća udobnost u radu ili imaju više vremena za privatne obveze. S druge strane, postoje zaposlenici koji preferiraju rad na klasičnom radnom mjestu, a kao prednosti takvog oblika rada ističu direktnu komunikaciju s kolegama, veću koncentraciju ili odvajanje poslovnog od privatnog života. Hibridan način rada izlazi ususret i zaposlenicima koji preferiraju rad na formalnom radnom mjestu, kao i zaposlenicima koji su radeći od kuće uslijed pandemije uvidjeli da im takav način rada bolje odgovara. Cilj ovog rada istražiti je i ispitati u kojoj je mjeri hibridan oblik rada povezan s radnom angažiranosti zaposlenika. Biti će provedeno empirijsko istraživanje čija je svrha utvrditi hoće li se angažiranost zaposlenika na poslu povećati ukoliko im organizacija pruži opciju izbora rada od kuće ili rada na klasičnom radnom mjestu.Working from home is a classic model of a flexible work arrangement created with the purpose of the employer providing flexibility and autonomy to his employees and gaining a competitive advantage on the labor market. With the advent of the COVID-19 virus pandemic, most companies were forced to adapt the dynamics of the work environment to new conditions. As a result, various new forms of flexible working mode are being introduced, among which it is worth highlighting the hybrid working mode – a combination of working from home and working at the workplace. Despite the challenges that working from home brings, many employees do not want to give up such a way of working because they consider themselves to be more productive in their work, have greater comfort at work or have more time for private obligations. On the other hand, there are employees who prefer to work in a classic workplace, and as advantages of this form of work they point out direct communication with colleagues, greater concentration or separation of business from private life.The hybrid way of working meets both employees who prefer to work in a formal workplace, as well as employees who, working from home due to the pandemic, realized that this way of working suits them better. The aim of this paper is to research and examine to what extent the hybrid form of work is related to the work engagement of employees. Empirical research will be conducted, the purpose of which is to determine whether the engagement of employees at work will increase if the organization gives them the option of choosing to work from home or work at a traditional workplace
Dysphagia screening in a nursing home
No full textDisfagija je poremećaj gutanja koji predstavlja simptom bolesti koji može zahvatiti područje usne šupljine, ždrijela, jednjaka te gastroezofagealnog spoja. Ona dovodi do mnogih negativnih posljedica i narušene kvalitete života što uključuje pothranjenost i dehidraciju, aspiracijsku pneumoniju, kronične upale pluća, narušeno opće zdravstveno stanje, gušenje pa i smrt. Prevalencija svih bolesti raste s porastom životne dobi pa tako i disfagija, a u posebno visokom riziku su osobe smještene u ustanove za starije i nemoćne. S obzirom na visoku prevalenciju disfagija kod osoba starije životne dobi, probirni protokol disfagija u domovima za starije i nemoćne osobe olakšao bi prepoznavanje znakova disfagije te rizičnih čimbenika odgovornih za njezin nastanak. Ranim prepoznavanjem mogućih smetnji gutanja, a potom i dijagnostikom mogle bi se prevenirati posljedične komplikacije, komorbiditeti, ali i poboljšati sigurnost i kvaliteta života pacijenata pružanjem potrebne intervencije. Cilj ovog rada je pomoću probirnih testova Ljestvice za procjenu hranjenja (engl. Eating Assessment Tool, EAT 10; Belafsky i sur. 2008.) i Upitnika za procjenu nutritivnog statusa (engl. Mini Nutritional Assessment, MNA; Nestle Nutritional Institute, 1994.) utvrditi rizik za nastanak poremećaja gutanja i/ili rane znakove poremećaja gutanja te dobiti uvid u prepoznatost, odnosno neprepoznatost rizika i/ili teškoća gutanja i nutritivni status na uzorku prikupljenom u domu za starije i nemoćne osobe. Također, cilj rada je provedbom Funkcionalne ljestvice oralnog unosa (engl. Functional Oral Intake Scale, FOIS; Crary i sur., 2005.) dokumentirati funkcionalne mogućnosti unosa sadržaja na usta, odnosno načine hranjenja korisnika doma za starije i nemoćne osobe. Na temelju provedenih upitnika izdvojit će se osobe rizične za razvoj disfagija. Ovim radom nastojat će se ukazati na važnost mogućeg ranog i pravovremenog prepoznavanja rizičnih čimbenika za razvoj poremećaja gutanja, problema i potreba osoba s poremećajima gutanja. S obzirom da u Republici Hrvatskoj trenutno još uvijek nije praksa zapošljavanje logopeda u ustanovama skrbi za starije i nemoćne osobe, ključan dio prevencije je i informiranje drugih stručnjaka u svrhu promicanja važnosti logopedske struke u prevenciji i intervenciji poremećaja gutanja u starijih osoba.Dysphagia is a swallowing disorder that appears as a symptom of different diseases that can affect the area of the oral cavity, pharynx, esophagus, and gastroesophageal junction. Dysphagia tends to leave many negative consequences and often impaires quality of life, causing malnutrition and dehydration, aspiration pneumonia, chronic pneumonia, impaired general health, suffocation and even death. The prevalence of all diseases is increased with age, including also dysphagia. Taking that into consideration elderly in nursing home settings are at a particularly high risk. Given the high prevalence of dysphagia in the elderly, a dysphagia screening protocol in nursing homes would facilitate the recognition of dysphagia signs and risk factors responsible for its occurrence. Early recognition of possible swallowing disorders and subsequent diagnosis could prevent consequent complications, comorbidities, but also improve the safety and quality of life of patients by providing the necessary intervention. The aim of this work is to determine the risk for the occurrence of swallowing disorders and/or early signs of swallowing disorders. Also, the insight into the recognition or non
recognition of the risk is gained, using the screening tests Eating Assessment Tool (Belafsky et al. 2008) and Mini Nutritional Assessment (Nestle Nutritional Institute, 1994) and/or difficulty swallowing and nutritional status on a sample collected in a nursing home. The goal of the work is also to document the functional possibilities of oral intake, i.e. the ways of feeding the users of the home for the elderly and infirm, by implementing the Functional Oral Intake Scale (Crary et al., 2005). Based on the completed assessment tools, people at risk for developing dysphagia will be singled out. This paper will try to point out the importance of possible early and timely recognition of risk factors for the development of swallowing disorders, problems and needs of people with swallowing disorders. Given that in the Republic of Croatia employing speech language pathologysts in nursing home settings is still not a practice, a key part of prevention is informing other experts in order to promote the importance of the speech language pathology profession in the prevention and intervention of swallowing disorders in the elderly
The effect of the probiotic strain Lactobacillus sp. and its exopolysaccharides on the inflammatory process in the intestine of C57BL/6J mouse
No full textUlcerozni kolitis je kronična upala debelog crijeva koja zahvaća sluznicu. Ulcerozni kolitis
obilježen je smanjenjem tjelesne težine, proljevom, krvavom stolicom, patohistološkim
promjenama na sluznici crijeva te različitim patofiziološkim procesima kao što je kronična upala,
oksidativni stres, stres endoplazmatskog retikuluma. Budući da je jedan od glavnih čimbenika ove
bolesti disbioza, odnosno smanjena raznolikost bakterija u crijevima, danas se kao mogući pristup
liječenja ulceroznog kolitisa istražuje obrada probioticima. Cilj ovog istraživanja bio je utvrditi
kakav utjecaj ima probiotički soj Limosilactobacillus fermentum i njegovi egzopolisaharidi na
dekstran natrij sulfatom (DSS) inducirani kolitis kod miševa soja C57BL/6J. Indeks razvoja kolitisa
praćen je mjerenjem gubitka težine, kozistencije stolice i krvarenja, a posljedice bolesti analizom
hematoloških, histoloških i molekularnih odrednica metodom kvantitativne lančane reakcije
polimerazom (qPCR). Rezultati ukazuju na djelomočno pozitivan učinak probiotičkog soja
Limosilactobacillus fermentum i njegovi egzopolisaharida na DSS-inducirani kolitis miševa soja
C57BL/6J kroz smanjenu razinu upale i krvarenja te regeneraciju tkiva sluzniceUlcerative colitis is a chronic inflammation of the large intestine restricted to the mucosa.
Ulcerative colitis is characterized by weight loss, diarrhea, bloody stools, pathohistological
changes in the intestinal mucosa and various pathophysiological processes such as chronic
inflammation, oxidative stress, and endoplasmic reticulum stress. Since one of the main factors of
this disease is dysbiosis, which is a reduced diversity of bacteria in the gut, today the use of
probiotics is being investigated as a potential approach for treating ulcerative colitis. The aim of
this research was to determine the impact of the probiotic strain Limosilactobacillus fermentum
and its exopolysaccharides on dextran sodium sulfate (DSS) induced colitis in C57BL/6J mouse.
The colitis activity index was monitored through measurements of weight loss, stool consistency,
and bleeding, while the disease outcomes were analyzed using hematological, histological, and
molecular markers through quantitative polymerase chain reaction (qPCR). The results indicate a
partially positive effect of the probiotic strain Limosilactobacillus fermentum and its
exopolysaccharides on DSS-induced colitis in C57BL/6J mice, manifested by reduced
inflammation and bleeding, as well as mucosal tissue regeneration
Imunosni odgovor riječnog raka na uzročnika bolesti račje kuge i njegove analoge
No full textRecently, immune memory in invertebrates has been demonstrated, revealing an improved
immune response to pathogen challenge after previous nonlethal exposures to the pathogen or
its analogues. However, this mechanism has been understudied in freshwater crayfish.
Therefore, in this study the effects of immune priming on the noble crayfish, Astacus astacus
were explored. Noble crayfish were primed with: i) crayfish saline solution, ii) beta-laminarin,
iii) inactivated Aphanomyces astaci hyphal suspensions and iv) inactivated A. astaci zoospores.
Then, the survival, and immediate and prolonged changes were monitored in the following
immunological parameters: total hemocyte count (THC), differential hemocyte count (DHC),
total protein content and gene expression of prophenoloxidase, immune system activator
C/EBP and immune system repressor Kr-h1. Hemolymph sampling was conducted 1, 4, 8, 24
hours and 16 days post-priming. Additionally, it was tested if priming could induce A. astaci
resistance as a long-term effect. The results indicate that immune priming has no effect on the
survival of the noble crayfish. Furthermore, the changes in the monitored immune parameters
of the noble crayfish are immediate and mostly return to normal values within 24 h. Finally,
results on the resistance to A. astaci remain inconclusive as no mortality due to infection was
observed.Nedavno je imunosna memorija dokazana kod beskralježnjaka, otkrivajući poboljšani
imunosni odgovor na infekciju patogenom nakon prethodnih nesmrtonosnih izlaganja
patogenu ili njegovim analozima. Međutim, ovaj mehanizam nedovoljno je istražen kod
slatkovodnih rakova. Stoga su u ovom radu istraženi učinci imunosne pripreme na riječnog
raka, Astacus astacus. Riječni rakovi su pripremljeni s: i) puferom (engl. crayfish saline
solution, CBS), ii) beta-laminarinom, iii) inaktiviranom suspenzijom hifa Aphanomyces astaci
i iv) inaktiviranim zoosporama A. astaci. Potom su praćeni preživljenje te neposredne i
dugotrajne promjene sljedećih imunoloških parametara: ukupni broj hemocita (THC),
diferencijalni broj hemocita (DHC), ukupni sadržaj proteina i ekspresiju gena
profenoloksidaze, aktivatora imunosnog sustava C/EBP i represora imunosnog sustava Kr-h1.
Uzorkovanje hemolimfe provedeno je 1, 4, 8, 24 sata i 16 dana nakon pripreme. Osim toga,
testirano je može li priprema izazvati otpornost na A. astaci kao dugoročni učinak. Rezultati
pokazuju da imunosna priprema nema utjecaja na preživljavanje riječnih rakova. Nadalje,
promjene praćenih imunosnih parametara riječnog raka su trenutne i većinom se vraćaju na
normalne vrijednosti unutar 24 sata. Naposljetku, rezultati otpornosti na A. astaci ostaju
nerazriješeni budući da nije primijećena smrtnost zbog infekcije
Laser ablation-inductively coupled plasma-mass spectrometry method in iron nanoparticles analysis
No full textU ovom radu sintetizirane su nanočestice neutralnog željeza (nZVI) za analizu sorpcije iona neodimija, europija, gadolinija, erbija i uranija iz vodene otopine na njihovu površinu. Sadržaj iona zaostao u vodenoj otopini određen je metodom spektrometrije masa uz induktivno spregnutu plazmu (ICP-MS), a sadržaj vezan na nanočestice željeza metodom spektrometrije masa uz induktivno spregnutu plazmu s laserskim otparavanjem (LA-ICP-MS). Ispitana je mogućnost uporabe polimliječne kiseline kao nosača čvrste faze za analizu metodom LA-ICP-MS. Zamijećena je loša reproducibilnost mjerenja te velika standardna odstupanja mjerenih signala. Za potrebe analize učinkovitosti sorpcije odabranih iona na nanočestice željeza metodom LA-ICP-MS načinjene su pastile uzoraka s mikrokristalnom celulozom. Pripravljena su tri kalibracijska standarda s mikrokristalnom celulozom i kalibracija je provedena uz željezo kao unutarnji standard. Pri analizi opažen je izvrstan linearni odziv te relativno nisko standardno odstupanje pri određivanju odabranih elemenata u tragovima. Analizom vodenih otopina lantanoida metodom ICP-MS nakon sorpcije, utvrđeno je da nZVI uklanjaju ione odabranih elemenata s vrlo visokom učinkovitošću.In this experiment nanoparticles of zero-valent iron (nZVI) were synthesized and a sorption of neodymium, europium, gadolinium, erbium and uranium ions from aqueous solution onto their surface was analyzed. Amount of ions that had remained in aqueous solution after the sorption was determined by inductively coupled plasma-mass spectrometry (ICP-MS), and amount of ions adsorbed onto the surface of nZVI by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). Applicability of polylactic acid as a solid carrier for LA-ICP-MS analysis was investigated, but poor measurement reproducibility and large standard deviation in measured signals were observed. Sample preparation for LA-ICP-MS analysis of bare nZVI included drying and homogenization by pressing nZVI with microcrystalline cellulose into pellets. Three calibration standards were prepared, and calibration was accomplished with iron as an internal standard. Highly linear response, and reasonably low standard deviations were observed during the analysis of the elements in ppm range. ICP-MS analysis of aqueous solutions after the sorption experiment showed very high sorption efficiency for all elements
Production and application of sophorolipids
No full textDanas se u industriji i proizvodnji sve više primjenjuje zelena kemija. Time se izbjegava upotreba kemijskih proizvoda i toksičnih otapala, te je veći naglasak na zaštitu okoliša i održivi razvoj. Biokataliza se može smatrati "zelenom kemijom" stoga se sve više primjenjuju biokatalitički procesi u industriji. U ovom radu, osim same biokatalize, opisani su i enzimi, njihova klasifikacija te primjena. U skladu sa zelenom kemijom predstavljeni su i soforolipidi, kao poznati biosurfaktanati koji se koriste zbog svoje minimalne ekotoksičnosti, visoke biorazgradivosti te dobre biokompatibilnosti. Soforolipidi pronalaze primjenu u raznim područjima industrije (farmaceutska, kemijska, prehrambena, kozmetička, poljoprivredna), u medici u liječenju raka, kao imunomodulatori i antivirusi, te u nanotehnologiji. U radu su predstavljene njihove prednosti i nedostaci, struktura te mogućnosti modifikacija. Također se opisuje i primjer dobivanja soforolipida procesom izolacije i pročišćivanja.Today, "green chemistry" has been increasingly applied in industry and manufacturing, which avoids chemical products and toxic solvents, emphasizing environmental protection and sustainable development. Biocatalysis is considered "green chemistry"; therefore, biocatalytic processes are increasingly applied in industry. In addition to biocatalysis, enzymes are also discussed in this work, along with their classification and where they are mainly used. Under the process of "green chemistry", sophorolipids (also known as biosurfactants), used due to their minimal ecotoxicity, high biodegradability, and good biocompatibility, are also described. Sophorolipids are utilized in various ways: industry (pharmaceutical, chemical, food, cosmetic, agricultural), cancer treatments (acting as immunomodulators and antivirals), and nanotechnology. This work explains advantages and disadvantages, structure, and modification of sophorolipids. Also, the method of obtaining sophorolipids by undergoing the process of isolation and purification is described
Application of metagenomic esterases for environmentally friendly degradation of polylactic acid
No full textPolimliječna kiselina (PLA) je biorazgradiv polimer čija su termička i mehanička obilježja slična masovno korištenoj plastici problematičnoj za zbrinjavanje. Biorazgradivosti i fizikalna svojstva čine PLA kandidatom za proizvodnju plastike koja se može razgraditi na okolišno prihvatljiv način. Enzimi koji razgrađuju PLA, za prihvatljivu okolišnu i industrijsku razgradnju, spadaju u skupinu α/β-hidrolaza. Trenutno je identificiran mali broj hidrolaza s aktivnošću prema PLA, a jednu od najvećih posjeduje nedavno otkriveni enzim MGS0156. U ovom diplomskom radu proizvedeni su MGS0156, njegov mutant i novi, do sada neokarakterizirani homolog, pronađen pretragom metagenomskih baza podataka. Hidrolitička aktivnost enzima prema PLA provjerena je u agaroznom gelu i slobodnoj suspenziji. Ovdje je prvi put pokazana aktivnost novog metagenomskog enzima prema PLA, koja se pokazala značajno većom od većine aktivnosti zabilježenih u literaturi. Računalnim metodama utvrđeno je da oba enzima imaju mobilni poklopac, identificirane su aminokiseline veznog mjesta s najvećim doprinosom vezanju supstrata i potencijalne mete za mutacije.Polylactic acid (PLA) is a biodegradable polymer with thermal and mechanical properties like those of widely used plastics with problematic disposal. Its biodegradability and physical properties make PLA a candidate for environmentally friendly plastic production. PLA-degrading enzymes used for environmentally friendly and industrial degradation, belong to the α/β-hydrolase group. A small number of PLA-hydrolases is identified, with one of the greatest activities belonging to a recently discovered MGS0156. Here, MGS0156, its mutant and a new, previously uncharacterized homologue discovered in metagenomic databases were produced. The hydrolytic activity towards PLA was tested in an agarose gel and a suspension. The hydrolytic activity of the new metagenomic enzyme was demonstrated for the first time and was found to be significantly higher than most activities documented in the literature. Using computational methods, it was found that both enzymes contain a mobile lid, binding site amino acids with the largest contribution to substrate binding were identified as well as potential mutation target
Ekotoksičnost mikroplastike i prioritetnih onečišćivala u vodi
No full textPlastics is an inevitable part of our daily life, hence its usage will continue to grow. Multiple and prolonged use and abrasion of the plastic surface might result in partial deterioration of plastic to micro-sized particles – microplastic (MP). Recently, it has been observed that MP’s multi-faceted structural and surface properties makes it an adsorbent for numerous aquatic pollutants such as pharmaceuticals and pesticides, defined under the EU water protection legislation as contaminants of emerging concern (CECs). Their hydrophobicity, polarity and low-biodegradability makes them readily adsorbable at polar, hydrophobic, aged and degraded specific surfaces of MP, contributing to the overall toxicity of such binary systems. Besides, in environmental conditions MP might leach additives and constituents that are often found toxic and hazard. The aim of this dissertation was to investigate the influence of thermal- and photo-aging of polyethylene terephthalate (PET) and polypropylene (PP) on the changes in morphology and structure of polymer materials and the overall ecotoxicity of PET and PP MPs in water. The characterization of pristine and aged MPs was performed by Fourier-transform infrared spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis (TGA), Scanning Electron Microscopy (SEM), as well as Water Contact Angle (goniometer) and the Branuer Emmett Teller (BET) specific surface area measurements. In order to investigate the fragmentation of plastic materials into MPs, grinding was performed in a single-drum cryogenic mill, while size distribution of obtained MPs particles was determined by the sieve shaker with five sieves of different mesh sizes to separate the particles according to their size. Adsorption of selected CECs, pharmaceutical diclofenac (DCF) and pesticide atrazine (ATZ), was investigated on both pristine and aged MPs according to the computational/empirical approach employing Full Factorial Design (FFD) as the experimental plan in the combination with Response Surface Modelling (RSM). Furthermore, pristine and aged MPs along with PP waste packaging films, were submitted to leaching tests in order to study possible migration of consituents. The main focus of this dissertation was the evaluation of the aquatic ecotoxicity of the samples after the adsorption and leaching tests and it was tested on the marine bacteria Vibrio fischeri (VF), freshwater crustacean Daphnia magna (DM) and green microalgae Raphidocelis subcapitata (RS), following the procedures disclosed in ISO 11348-3:2007, ISO 6341:2012 and ISO 8692:2012 standards, respectively. Finally, the leachates were tested for their biodegradability, along with glucose as readiliy biodegradable substrate. Based on the obtained results, it is possible to establish a direct relationship between the aging of MP and the increase in its toxicity. Characterization revealed severe degradation of material; thermal-aging affected the structure, while photo-aging caused the surface alterations of PET and PP. Hence, changes in surface morphology such as cracks, fractures, notches and bumps were observed.
The increase in crystallinity of PET and PP resulted in changes of brittleness and accelerated fragmentation to smaller MP’s particles. It was found that hydrophobicity increased, while specific surface decreased; the exception was photo-aged PP. Adsorption of CECs onto MPs is correlated with the changes in the surface morphology enhanced with the photo-aging. Adsorption of CECs was driven by hydrophobicity and specific surface, as well as smaller MP particle sizes as a result of accelerated and prolonged aging period.
RSM approach revealed that temperature is a more significant parameter than MP dosage for CECs adsorption. It can be concluded that aquatic ecotoxicity generally increases with the prolonged exposure to aging, especially valid for the photo-aged MPs. However, some exceptions were observed depending on the type of MPs, CECs and targeted toxicity test organism. Individual CECs showed high ecotoxicity effects toward DM, while slightly lower effects were recorded toward RS. It was also found that DM was the most sensitive organism to the exposure to MPs, with and without CECs. The aging of MPs resulted with the accelerated leaching of constituents for both PET and PP, resulting with ecotoxic responses in cases of all three tested organisms. However, DM was shown to be the most sensitive to leachates originated from PP-MP, while in the case of PET leachates other two test organisms (VF and RS) were more sensitive in ecotoxicity response than DM.
The biodegradability of glucose was inhibited by the presence of (heavy) metals in leachates originated from both thermal- and photo-aged PET and PP MPs.Plastika je neizbježan dio svakodnevnog života i smatra se kako će njezina uporaba nastaviti rasti. Višestruka i dugotrajna uporaba te abrazija površine plastike može rezultirati djelomičnom fragmentacijom na čestice mikro veličine – mikroplastiku (MP). Nedavno je uočeno kako mikroplastika ima brojna strukturna i površinska svojstva koja je čine adsorbentom za brojna onečišćivala pristutna u vodi kao što su farmaceutici i pesticidi, koji su prema vodnom zakonodavstvu EU-a definirani kao onečišćivala koja izazivaju zabrinutost (eng. Contaminants of Emerging Concern, CEC). Njihova hidrofobnost, polarnost i slaba biorazgradivost čine ih toksičnima, a lako se apsorbiraju na polarnu, hidrofobnu, ostarenu i degradiranu specifičnu površinu MP. U okolišnim uvjetima može doći i do izluživanja (eng. leaching) aditiva te konstituenata koji mogu biti ekotoksični i opasni za organizme.
Cilj ove disertacije bio je istražiti utjecaj termo- i foto- starenja poli(etilen- tereftalata) (PET) i polipropilena (PP) na promjenu morfologije i strukture materijala te ekotoksičnost mikroplastike u vodi. Karakterizacija nestarene i starene MP provedena je pomoću infracrvene spektroskopije s Fourierovom transformacijom (FTIR), diferencijalne pretražne kalorimetrije (DSC), termogravimetrijske analize (TGA), skenirajuće elektronske mikroskopije (SEM), kao i goniometra za određivanje kontaktnog kuta vode te mjerenjem specifične površine na temelju Branuer Emmett Teller (BET) modela. Kako bi se istražila fragmentacija plastike u MP, usitnjavanje je provedeno u kugličnom kriogenom mlinu, dok je raspodjela veličine dobivenih MP čestica određena pomoću vibracijske tresilice s pet sita različitih veličina otvora za izdvajanje čestica prema njihovoj veličini. Adsorpcija CEC-a, farmaceutika diklofenaka (DCF) i pesticida atrazina (ATZ) ispitana je i na nestarenoj i starenoj MP u skladu s računalnim/empirijskim pristupom na temelju punog faktorskog dizajna (eng. Full Factorial Design, FFD) u kombinaciji s metodologijom odzivne površine (eng. Response Surface Methdology, RSM). Nadalje, nestarena i starena MP zajedno s otpadnim ambalažnim PP filmovima, podvrgnuti su testovima izluživanja kako bi se ispitala moguća migracija konstituenata. Glavni fokus ove disertacije bila je procjena ekotoksičnosti uzoraka u vodi nakon provedenog procesa adsorpcije i izluživanja i to na morskim bakterijama Vibrio fischeri (VF), slatkovodnim račićima Daphnia magna (DM) i zelenim mikroalgama Raphidocelis subcapitata (RS), prema standardima ISO 11348-3: 2007, norme ISO 6341:2012 i ISO 8692:2012. Na kraju, ispitana je i biorazgradivost uzoraka nakon testa izluživanja, zajedno s glukozom kao lako biorazgradivim supstratom. Na temelju dobivenih rezultata, moguće je utvrditi izravnu vezu između starenja MP- i povećanja njezine toksičnosti. Karakterizacija je pokazala da su procesi termooksidacije i fotooksidacije uzrokovali degradaciju materijala, gdje je termooksidacija utjecala na strukturu, dok je fotooksidacija uglavnom utjecala na površinske promjene PET- i PP-. Stoga su uočene promjene u morfologiji površine kao što su pukotine, lomovi, zarezi i neravnine. Povećanje kristalnosti PET-a i PP-a rezultiralo je promjenom lomljivosti i ubrzanom fragmentacijom na manje čestice MP-a. Uočeno je je povećanje hidrofobnosti i smanjenje specifične površine, osim u slučaju starenog PP-a. Adsorpcija CEC-ova na površinu MP-a u korelaciji je s promjenama morfologije površine nastalim fotooksidativnim starenjem. Hidrofobnost i specifična površina, zajedno s manjim veličinama čestica starenog MP-a, potaknuli su adsorpciju hidrofobnih CEC-ova. RSM ukazuje na to kako je temperatura značajniji parametar od udjela MP za adsorpciju CEC-ova. Može se zaključiti da vodena ekotoksičnost općenito raste s produljenom izloženošću starenju, posebno za foto-stareni MP. Međutim, primijećene su neke iznimke ovisno o vrsti MP-a, CEC-a i ciljanog organizma za ispitivanje ekotoksičnosti. Pojedinačni CEC-ovi pokazali su visoke ekotoksične učinke prema DM, dok su nešto niži učinci zabilježeni prema RS. Također je utvrđeno da je DM najosjetljiviji organizam na izloženost MP, sa i bez CEC-ova. Posebno je DM pokazala visoku osjetljivost na MP, sa i bez adsorbiranih CEC-ova.
Starenje MP rezultiralo je pojačanim izluživanjem konstituenata iz PET-a i PP-a, što je rezultiralo ekotoksičnim odgovorima u slučajevima sva tri testirana organizma. Međutim, pokazalo se kako je DM najosjetljiviji na izluživanje PP-MP, dok su u slučaju izluživanja
PET-MP osjetljivija druga dva testna organizma (VF i RS). Biorazgradivost glukoze bila je inhibirana prisutnošću (teških) metala u uzorcima nakon izluživanja koje potječu iz termo- i foto-starenih PET-MP i PP-MP
Optimization of cardiovascular risk factor management in patients with BCR::ABL1 negative chronic myeloproliferative neoplasms, current knowledge, and perspectives
No full textThe exact prognostic role of cardiovascular (CV) risk factors in patients with BCR::ABL1 negative chronic myeloproliferative neoplasms (MPNs) remains unknown as it is often masked by other MPN-related features that bear strong prognostic impact on thrombotic risk. Therefore, current MPN treatment is not primarily guided by presence of CV risk factors. Treatment of CV risk factors in MPN patients usually mirrors that from the general population, despite the fact that CV risk factors in MPNs have their own specificities. Moreover, the optimal target levels for different metabolic deflections in MPNs (i.e., low-density lipoprotein, serum uric acid, or glycated hemoglobin levels) have not been defined. In the current review, we separately discuss the most important aspects of every individual CV risk factor (arterial hypertension, hyperlipidemia, chronic kidney disease, smoking, diabetes mellitus, hyperuricemia, and obesity and cachexia) in MPNs, summarize recent advances in the field, and propose future directions and research areas which may be needed to appropriately manage CV risk factors in MPNs