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Sedation options in a cardiac catheterization laboratory and coronary care unit: protocol review and clinical experience from General Hospital Slavonski Brod
No full textEmergencies in Pediatric Endocrinology
No full textHitna su stanja u pedijatrijskoj endokrinologiji rijetka, životno opasna stanja koja često ostaju neprepoznata. Zakašnjela dijagnoza i odgoda liječenja dodatno pridonose smrtnosti koja je u ovim stanjima ionako visoka. Endokrinološka hitna stanja mogu biti akutna komplikacija podliježuće endokrinopatije, ali često i prva prezentacija nedijagnosticiranog endokrinog poremećaja. U ovom preglednom članku prikazani su klinička slika, dijagnoza i liječenje dijabetičke ketoacidoze (DKA), adrenalne insuficijencije i tireotoksične krize. DKA je najčešće hitno stanje u pedijatrijskoj endokrinologiji. Bolest je obilježena hiperglikemijom, acidozom, ketozom i dehidracijom. Temeljni principi liječenja dijabetičke ketoacidoze uključuju nadoknadu tekućine, primjenu inzulina i korekciju elektrolitskog disbalansa. Nadoknada tekućine najvažnija je komponenta u liječenju dijabetičke ketoacidoze. Adrenalna kriza i tireotoksična kriza rijetka su stanja, a nepravovremeno prepoznavanje ovih hitnih stanja povezano je s visokom smrtnošću.Emergencies in paediatric endocrinology are rare, life-threatening conditions that often remain unrecognized. Delayed diagnosis and delayed treatment further contribute to mortality, which is already high in these conditions. Endocrine emergencies can be an acute complication of an underlying endocrinopathy, but often also the first presentation of an undiagnosed endocrine disorder. This review article presents the clinical picture, diagnosis and treatment of diabetic ketoacidosis (DKA), adrenal insufficiency and thyrotoxic crisis. DKA is the most common emergency in paediatric endocrinology. It is characterized by hyperglycemia, acidosis, ketosis and dehydration. The basic principles of DKA treatment include fluid replacement, insulin administration, and correction of electrolyte imbalance. Fluid replacement is the most important component in the treatment of DKA. Adrenal crisis and thyrotoxic crisis are rare conditions, and untimely recognition of these emergencies is associated with high mortality
Extracellular Vesicles in Therapy of Neurodegenerative Diseases
No full textPotpuni gubitak ili disfunkcija neurona glavna su obilježja neurodegenerativnih bolesti, koje uključuju Alzheimerovu bolest, Parkinsonovu bolest, amiotrofičnu lateralnu sklerozu, Huntingtonovu bolest i druge. Trenutačno ne postoje mogućnosti potpunog zaustavljanja ili preokretanja tijeka ovih bolesti te je postojeća terapija većinom simptomatska. No, u zadnje se vrijeme pojavljuju nove terapijske platforme bazirane na izvanstaničnim vezikulama. Izvanstanične vezikule su prirodne nanotvorevine svih stanica te su vrlo perspektivne u terapiji neurodegenerativnih bolesti zbog svoje male imunogenosti, ciljanih djelovanja na stanice te mogućnosti lakog prolaska tjelesnih barijera uključujući i krvno-moždanu barijeru. One transportiraju svoj teret izravno do neurona, astrocita ili glija-stanica, a to uključuje lijekove, proteine, mikroRNA i male interferirajuće RNA. Nadalje, njihova se površina može modificirati kako bi se poboljšala dostava u područja mozga zahvaćena neurodegeneracijom. Postojeća pretklinička istraživanja pokazala su da tretmani putem izvanstaničnih vezikula utječu na preživljavanje neurona, smanjuju agregaciju proteina te moduliraju neuroinflamaciju. Međutim, u smislu kliničke translacije postavljaju se neka pitanja poput efikasnosti ubacivanja malih molekula u izvanstanične vezikule ili njihove dugoročne sigurnosti. Zaključno, izvanstanične vezikule predstavljaju novi, revolucionarni terapijski pristup u kompleksnoj patofiziologiji neurodegenerativnih bolesti.The complete loss or dysfunction of neurons is the main feature of neurodegenerative diseases, which include Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, Huntington's disease, and some others. At present, there are no available options to completely stop or reverse the progression of these diseases, and current therapies are mainly symptomatic. However, recently new therapeutic platforms based on extracellular vesicles have emerged. Extracellular vesicles are natural nanovesicles produced by all cells and are very promising in the therapy of neurodegenerative diseases due to their low immunogenicity, targeted actions on cells, and the ability to easily cross bodily barriers, including the blood-brain barrier. They transport their cargo directly to neurons, astrocytes, and glial cells, which may include drugs, proteins, microRNAs, and small interfering RNAs. Furthermore, their surface can be modified to enhance the delivery to specific areas of the brain affected by neurodegeneration. Preclinical studies have demonstrated that treatments using extracellular vesicles enhance neuron survival, reduce protein aggregation, and modulate neuroinflammation. However, in terms of clinical translation, some questions arise regarding the efficacy of introducing small molecules into extracellular vesicles or their long-term safety. In conclusion, extracellular vesicles represent a new, revolutionary therapeutic approach within the complex pathophysiology of neurodegenerative diseases
Nedavni napreci u katalitičkoj epoksidaciji oleinske kiseline za sintezu biopoliola: izazovi i mogućnosti
No full textThe catalytic epoxidation of oleic acid is a key process in bio-polyol synthesis, offering a renewable alternative to petroleum-based materials. This review explores recent advances in catalyst development, process optimisation, and kinetic modelling, with an emphasis on the transition from conventional homogeneous catalysts to more sustainable heterogeneous alternatives, such as zeolites and metal oxides. Key factors influencing reaction efficiency, including catalyst stability, oxirane retention, and by-product control, are critically analysed. The discussion also highlights industrial applications and potential improvements to enhance process scalability and economic feasibility. This review provides insights into overcoming current challenges and advancing sustainable bio-polyol production.Katalitička epoksidacija oleinske kiseline ključan je proces u sintezi biopoliola te predstavlja obnovljivu alternativu materijalima dobivenim iz nafte. Ovaj pregledni rad obuhvaća najnovije napretke u razvoju katalizatora, optimizaciji procesa i kinetičkom modeliranju, s naglaskom na prijelaz s konvencionalnih homogenih katalizatora na održivije heterogene sustave poput zeolita i metalnih oksida. Kritički se analiziraju ključni čimbenici koji utječu na učinkovitost reakcije, uključujući stabilnost katalizatora, očuvanje oksiranskog prstena i kontrolu nusprodukata. U radu se raspravlja i o industrijskim primjenama te potencijalnim poboljšanjima koja mogu unaprijediti skalabilnost procesa i njegovu ekonomsku isplativost. Ovaj pregled pruža uvid u načine prevladavanja postojećih izazova i daljnjeg razvoja održive proizvodnje biopoliola
Improving anchorage occupancy forecasting with stacked ensemble learning
Get PDFAnchorage areas are essential for safe and efficient maritime operations. However, conventional forecasting models often underperform in dynamic port conditions, as they rely heavily on historical averages and static assumptions. To address these limitations, this study proposes a forecasting framework for anchorage occupancy. This framework uses stacked ensemble learning, integrating both statistical and machine learning models to enhance predictive accuracy and operational reliability. The proposed approach was applied to occupancy data from the E1 anchorage at Ulsan Port, with performance evaluated across various forecasting models and ensemble strategies. In addition, a hexagon-based occupancy estimation method was implemented to assess spatial efficiency and safety in comparison to the traditional anchor circle method. The results demonstrate that the stacking ensemble model effectively captures complex, nonlinear patterns in vessel traffic and delivers improved forecasting performance. These findings highlight the practical potential of stacking ensemble techniques and spatial modeling innovations in enabling proactive anchorage management, reducing congestion, and enhancing maritime safety in real-world port environments
Aktualnosti iz projekta “Znanje+Kreativnost = STEM Inspiracija”: Kalendar događanja siječanj 2026. (“Znanje+Kreativnost = STEM Inspiracija”)
Get PDFCardiovascular Response in Partly Mechanized Willow Planting Operations Indicates a Low to Moderate Intensity of Work
Get PDFFast growing species such as willow have been found to be a viable alternative for bio-energy production. Establishment of willow crops requires a series of operations, among which planting is important for their success. Partly mechanized planting has been studied lately in terms of productivity and costs, and it was found to be a viable alternative for small and dispersed plots. However, no research has addressed its suitability in terms of work intensity. One important assumption is that physical strain would be higher in such operations, mainly due to an intense use of the upper limbs, probably leading to a high cardiovascular workload. This study evaluated the level of physical workload in partly mechanized willow planting operations by heart rate measurements taken on six subjects, which were observed during all the common planting tasks. Close to 65 hours of observations were taken at a rate of one second, and the heart rate increment was used as the main indicator to characterize the workload of planting work. The findings indicate that there was a task-based variability in cardiovascular response (ca. 87 to 96 bpm) and in the heart rate increment among the subjects (ca. 14 to 28%). In addition, there was a differentiation in terms of heart rate increment among the planting tasks. Nevertheless, most of the data indicated a low to moderate cardiovascular workload. Although these results validate partly mechanized planting as a suitable alternative in terms of cardiovascular output, future studies should evaluate other ergonomic conditions such as the biomechanical exposure and the risks of developing musculoskeletal disorders
GEOTEHNIČKA SVOJSTVA I PRIMJENA U IZGRADNJI CESTA LATERITNOGA TLA POBOLJŠANOGA JALOVINOM OD FLOTACIJE ŽELJEZNE RUDE
No full textThe abundance of lateritic soils in Nigeria has made them one of the most used materials for road construction. However, many of these soils exhibit substandard geotechnical properties, necessitating improvements before their deployment in road construction. This study aims to evaluate the geotechnical properties and practical applications of iron ore tailings (IOTs)-amended lateritic soils for road construction. The lateritic soil obtained from a road construction burrow-pit as well as the mixture with IOTs were subjected to mineralogical and geotechnical tests. The lateritic soil contains appreciable amounts of clay (29.1%), fines (52.4%) and sand (46.6%) with a small quantity of gravel (1.0%). Thus, they can be described as clayey sand. In addition, an investigation of its consistency limits indicates that the soil plots above the A-line and classified as highly plastic clay based on their position on the Unified Soil Classification System (USCS) chart. The results of the geotechnical properties indicate a significant improvement in the geotechnical properties of the lateritic soil with the addition of IOT. There was an increase in maximum dry density and California bearing ratio (CBR) with a reduction in the values of liquid limit, plasticity index, linear shrinkage, and unconfined compressive strength. This study demonstrates that the geotechnical properties of the lateritic soil can be modified to fulfil the standard required for utilization as a road subbase and the minimum required can be suitably achieved by mixing about 20% IOTs with lateritic soil.Velika rasprostranjenost lateritnih tala u Nigeriji učinila ih je jednim od najčešće korištenih materijala za izgradnju cesta. Međutim, mnoga od tih tala pokazuju nezadovoljavajuća geotehnička svojstva, zbog čega je prije njihove primjene u cestogradnji nužno provesti poboljšanja. Cilj je ovoga istraživanja ocijeniti geotehnička svojstva i praktičnu primjenu lateritnoga tla poboljšanoga jalovinom od flotacije željezne rude (IOT) u svrhu izgradnje cesta. Lateritno tlo prikupljeno iz iskopa za cestogradnju, kao i njegove mješavine s jalovinom od flotacije željezne rude, podvrgnuti su mineralnim i geotehničkim ispitivanjima. Lateritno tlo sadržavalo je znatan udio gline (29,1 %), sitnih frakcija (52,4 %) i pijeska (46,6 %) uz manju količinu šljunka (1,0 %), pa se može klasificirati kao glinoviti pijesak. Nadalje, analiza granica konzistencije pokazala je da tlo prema položaju na USCS (Unified Soil Classification System) dijagramu leži iznad A-linije te se klasificira kao glina visoke plastičnosti. Rezultati geotehničkih ispitivanja uputili su na znatna poboljšanja svojstava lateritnoga tla dodatkom jalovine od flotacije željezne rude. Utvrđen je porast maksimalne suhe gustoće i CBR (California Bearing Ratio) vrijednosti, uz smanjenje vrijednosti granice tečenja, indeksa plastičnosti, linearnoga skupljanja i jednoosne tlačne čvrstoće. Ovo istraživanje pokazuje da se geotehnička svojstva lateritnoga tla mogu modificirati tako da zadovolje standarde potrebne za primjenu u sloju donje podloge kolnika, a minimalni zahtjevi mogu se postići dodavanjem oko 20 % jalovine od flotacije željezne rude u lateritno tlo
Understanding the Core Values of Seafarers: A Study Based on Schwartz’s Value Theory
Get PDFValues of seafarers influence the safety of maritime operations and determining them helps in understanding seafarers’ behavior and decision-making. This empirical study investigated the predominant personal values among seafarers using Schwartz’s Value Theory as the theoretical framework. Employing a quantitative approach, this study surveyed 1002 seafarers using a revision of the Schwartz Revised Portrait Value Questionnaire (PVQ-RR). The revised version (in English) was tested for validity and reliability and was pilot tested, then translated into eight other languages. Quantitative analysis involved statistical analyses which followed the recommendations of Schwartz (2021) to determine the values that seafarers hold, including their significant differences based on demographic profiles. The findings reveal that the predominant values among seafarers are Self-transcendence and Conservation, specifically Security, Benevolence, Universalism and Conformity broad values. Universalism-Nature, Security-Personal, Benevolence-Caring, Security-Societal, Benevolence-Dependability and Universalism-Concern were the narrowly defined values that seafarers hold. Also, there was no significant difference in the values that seafarers hold in terms of their demographic profile except for their nationality. To the knowledge of the researchers, this is the first study that used the 19 value-framework to determine the value priorities of seafarers. The determined values of seafarers are significant to maritime stakeholders, including the Maritime Education and Training institutions in designing/redesigning programs to address the affective domain of learning, specifically values and their internalization