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Burnout, school engagement and life satisfaction of gymnasium (grammar school) graduates in the context of the Demands-Resources model
No full textOvim istraživanjem nastojao se provjeriti model zahtjeva i resursa (SD-R) u školskom kontekstu odnosno ispitati medijacijska uloga sagorijevanja i školskog angažmana u odnosu zahtjeva i resursa sa zadovoljstvom životom. Istraživanje je provedeno u četiri srednje škole u Hrvatskoj na 233 učenika četvrtih razreda gimnazijskog smjera koji su ispunili demografske podatke, Upitnik školskih zahtjeva i resursa, 12-čestičnu GRIT ljestvicu, Inventar sagorijevanja u školi, Inventar školskog angažmana i Skalu zadovoljstva životom. Za analizu prikupljenih podataka korištena je medijacijska analiza. Anksioznost oko izbora karijere negativno korelira s podrškom nastavnika, mentalni zahtjevi pozitivno s podrškom roditelja te je stil rada negativno povezan s mogućnosti razvoja i podrškom nastavnika. Nadalje, nakon provjere učinka zahtjeva i resursa na sagorijevanje i školski angažman pokazalo se kako svi zahtjevi, a to su anksioznost oko izbora karijere, mentalni zahtjevi i stil rada koji se odnosi na očekivanja o količini i tempu izvršavanja školskih obaveza, imaju pozitivni izravni učinak na sagorijevanje. Od resursa, mogućnost razvoja i dosljednost interesa imaju negativni izravni učinak na sagorijevanje. Dobiveno je kako podrška nastavnika, mogućnost razvoja i ustrajnost u zalaganju kao varijable resursa imaju pozitivni izravni učinak na školski angažman. Od zahtjeva, samo stil rada ima negativni izravni učinak na školski angažman. Na zadovoljstvo životom anksioznost oko izbora karijere i stil rada imaju negativni izravni učinak, dok samo podrška roditelja ima pozitivni izravni učinak. Izravni učinci sagorijevanja i školskog angažmana na zadovoljstvo životom nisu se pokazali značajnima, kao niti neizravni učinci zahtjeva i resursa putem sagorijevanja i školskog angažmana na zadovoljstvo životom. Neznačajni neizravni učinci upućuju da sagorijevanje i školski angažman ne posreduju u odnosu zahtjeva i resursa te zadovoljstva životom kako je pretpostavljeno modelom. Dobiveni rezultati upućuju na važnost ispitivanja modela zahtjeva i resursa u školskom kontekstu te mogu poslužiti kao smjernice u izradi programa prevencije za rad na smanjenju negativnih učinaka školskih zahtjeva i razvoju osobnih i okolinskih resursa.The aim of this study was to test the adequacy of the Demands−Resources model (SD-R) in a school context, as well as to examine the mediating role of burnout and school engagement in the relationship between demands and resources and life satisfaction. The study was carried out in four secondary schools in Croatia on 233 fourth grade gymnasium students who filled out the demographic data, the School Demand−Resource Questionnaire, the 12-item GRIT scale, the School Burnout Inventory, the School engagement inventory and The Satisfaction With Life Scale. Mediation analysis was done to analyze the collected data. Career choice anxiety negatively correlates with teacher support, mental demands correlate positively with parent support and work style is negatively correlated with the possibility of development and teacher support. Furthermore, after examining the effects of demands and resources on burnout and school engagement, it was shown that all demands, career choice anxiety, mental demands and work style which refers to expectations of the amount and schoolwork pace, have a positive direct effect on burnout. Regarding resources, the possibility of development and consistency of interests have a negative direct effect on burnout. It was found that teacher support, the possibility of development and perseverance in effort as resource variables have a positive direct effect on school engagement. Regarding demands, only work style has a negative direct effect on school engagement. Furthermore, career choice anxiety and work style have a negative direct effect, while only parent support has a positive direct effect on life satisfaction. The direct effects of burnout and school engagement on life satisfaction were not significant and indirect effects of demands and resources on life satisfaction through burnout and school engagement were also not significant. The not-significant indirect effects indicate that burnout and school engagement do not mediate the relationship between demands and resources on one side and life satisfaction on the other side as assumed by the model. However, the obtained results indicate the importance of examining the Demands−Resources model (SD-R) in a school context and can serve as guidelines for the development of prevention programs to work on reducing the negative effects of school demands and on development of personal and external resources
Rezultati eksperimenata čistog savijanja aluminijskih uzoraka s perforacijama u jednom i četiri reda.
No full textOvaj skup podataka sadrži neobrađene rezultata eksperimenta čistog savijanja na dvije vrste perforiranih aluminisjkih uzoraka. Ispitivani su aluminijski uzorci s jednim redom perforacija i s četiri reda perforacija, analogno nazvani B1 i B4. Testovi na uzorcima B1 provedeni su u Centru za mikro- i nanoznanosti i tehnologijevi, a testovi na uzorcima B4 na Građevinskom fakultetu Sveučilišta u RIjeci. Ovi testovi provedeni su u svrhu određivanja karakteristične duljine za savijanje i mjere popvezanosti mikrorotacije i makrorotacije promatrane mikrostrukture.Stanje čistog savijanja u testiranim uzorcima proizvedeno je nanošenjem opterećenja u četiri točke (eng. four-point bending). Svi testovi provedeni su u linearno elastičnoj zoni te zaostale deformacije nisu uočene. Za svaku vrstu uzoraka testirana su tri različita primjerka (u podatcima nazvani 1, 2 i 3) od kojih je svaki testiran na tri različita raspona između točki opterećenja, (u podatcima označeni slovima od A do C, od najvećeg raspona do najmanjeg). Uzorci B1 testirani su pomoću kidalice Shimadzu Autograph AGS-X, a uzorci pomoću kidalice Zwick/Roell Z600E. Podatcima su priložene sheme postava eksperimenata
Apron conveyor for municipal waste
No full textOvaj diplomski rad bavi se konstrukcijom pločasto-člankastog transportera za prijenos komunalnog otpada. Pločasto-člankasti transporteri pripadaju skupini sustava za neprekidni transport raznih vrsta materijala, a pri njihovoj izradi korišteni su standardni konstrukcijski elementi. Drugo poglavlje daje kratak pregled povijesnog razvoja transporta, s naglaskom na vrste transporta koje se dijele na neprekidne i povremene. U tom poglavlju detaljno su opisani najčešće korišteni sustavi neprekidnog transporta, među kojima dominiraju trakasti transporteri. Također se razmatra konstrukcija člankastih transportera, njihova prednost i nedostaci. U trećem poglavlju objašnjeni su koraci proračuna svih dijelova transportera, koji uključuju određivanje nosive konstrukcije, odabir standardnih dijelova i dizajn nestandardnih komponenti, čime se osigurava optimalna funkcionalnost sustava.This thesis focuses on the design of a plate-link conveyor for the transport of municipal waste. Plate-link conveyors belong to the group of systems for continuous transport of various types of materials, and standard construction elements were used in their design. The second chapter provides a brief overview of the historical development of transportation, with an emphasis on the types of transport, which are divided into continuous and intermittent. This chapter describes in detail the most commonly used continuous transport systems, with belt conveyors being the dominant type. The construction of link conveyors, their advantages, and disadvantages are also discussed. The third chapter explains the steps involved in calculating all parts of the conveyor, including determining the load-bearing structure, selecting standard components, and designing non-standard components, ensuring the optimal functionality of the system
Modelling of inox tabel positions with protective wall using sheet metal tools in forming technology
No full textU ovome radu zadatak je bio modeliranje inox pozicija stola sa zaštitom zida primjenom Sheet
Metal alata u programu SolidWorks. Upotreba Sheet Metal alata u tehnologiji oblikovanja lima
značajno je pridonjela pojednostavljenju izrade sklopa retropulta od lima, kao i CAD softwer. Na
samom početku rada opisane su fizikalne promjene deformacije lima i opisane su pojedine metode
obrade lima kao što su: savijanje lima, duboko vučenje i razne metode rezanja (odvajanja) lima.
Nadalje je dan opis zadatka projekta, odabir materijala čelika i njegov opis, te sažetak programa
SolidWorks. Zatim slijedi detaljan prikaz izrade svih dijelova, podsklopova i sklopova inox
retropulta.In this paper, the task was to model stainless steel table positions with wall protection using the
Sheet Metal tool in SolidWorks. The use of the Sheet Metal tool in sheet metal forming technology
has significantly contributed to simplifying the assembly of stainless steel back bar counter, as
well as CAD software.
At the beginning of the paper, the physical changes in sheet metal deformation are described, along
with various sheet metal processing methods such as bending, deep drawing, and different cutting
(separating) techniques. Furthermore, the project task is explained, including the selection and
description of the steel material, as well as a summary of the SolidWorks software.
This is followed by a detailed presentation of the creation of all parts, subassemblies, and
assemblies of the stainless steel back bar counter
The impact of carbon prices on the power sector
No full textU ovom diplomskom radu analiziran je sve značajni utjecaj cijena emisija CO2 na elektroenergetski sektor, kojima se teži ostvariti globalne klimatske ciljeve i tranziciju prema održivoj proizvodnji električne energije. Opisane su karakteristike i promjene utjecaja emisija CO2 te najveći emiteri iz elektroenergetskog sektora. Početak kontrole i osvještavanje potrebe za smanjenjem emisije obilježili su globalni klimatski sporazumi i inicijative odnosno Kyoto protokol, Pariški sporazum i Zelenog plan koji su služili kao osnova za početak naplate emisija koje se ispuštaju u atmosferu. Kao glavni alat oformljeni su sustavi trgovanja emisijskih dozvolama čije su karakteristike i načini djelovanja detaljno opisani na primjeru više sustava, posebna pažnja posvećena je EU-ETS koji ima značajan utjecaj na elektroenergetski sustav Republike Hrvatske. Također prikazano je funkcioniranje tržišta električne energije kako bi se uvidjelo kako promjene cijena CO2 ne samo da mijenja tržište već utječe na sudionike proizvodnje, prijenosa i distribucije električne energije. U radu je analiziran utjecaj sustava trgovanja emisijama CO2 na primjeru Republike Hrvatske i njenog okruženja. S obzirom na povezanost i specifične karakteristike sustava koji se oslanja na proizvodnju termoelektrana na ugljen i plin, neke države podliježu plaćanju cijene emisijskih dozvola dok su druge izvan EU-ETSa. Istražen je utjecaj promjena cijena emisijskih dozvola na proizvodni miks te koliki učinak postižu s obzirom na ograničenja sustava. Da zaključimo, uvođenje cijena na emisijske dozvole izaziva značajne promjene na elektroenergetski sustav, potiču implementaciju čišćih oblika proizvodnje energije no zbog specifičnosti promatranog sustava i njegove ovisnosti o termoelektranama koje su najveći zagađivači utjecaj cijena je ograničen te prekomjerno povećanje ne može ostvariti efektivno smanjenje zagađenja već stvara opterećenje na sustav.This master's thesis analyzes the significant impact of CO2 emission prices on the electricity sector, which aims to achieve global climate goals and the transition to sustainable electricity production. It describes the characteristics and effects of CO2 emissions, highlighting the largest emitters in the electricity sector. The beginning of control and awareness of the need to reduce emissions were marked by global climate agreements and initiatives, as the Kyoto Protocol, the Paris Agreement, and the Green Plan, which served as the basis for the beginning of charging for emissions released into the atmosphere. Emissions trading systems were established as the main tool, the characteristics and methods of operation of which are described in detail on the example of several systems, special attention is paid to the EU-ETS, which has a significant impact on the electricity system of the Croatia. The functioning of the electricity market is also presented to see how changes in CO2 prices not only change the market but also affect participants in the production, transmission and distribution of electricity. The paper analyzes the impact of the CO2 emissions trading system on the example of the Republic of Croatia and its environment. Given the interconnectedness and specific characteristics of the system that relies on coal and gas-fired thermal power plants, some countries are subject to the payment of emission allowance prices while others are outside the EU-ETS. The influence of emission allowance price fluctuations on the production mix and their effects within the system's constraints have been analyzed. To conclude, the implementation of emission allowance prices causes significant changes in the electricity system, encouraging the implementation of cleaner forms of energy production, still due to the specificity of the observed system and its dependence on thermal power plants, which are the largest polluters, the impact of prices is limited and excessive increases cannot achieve effective pollution reduction but rather create a burden on the syste
Key priorities for the implementation of the 2023 ESC Guidelines for the management of endocarditis in low-resource settings
No full textAbstract European Society of Cardiology (ESC) Guidelines provide best practice, evidence-based recommendations for diagnosing and treating patients with cardiovascular diseases. It is not always possible for best practices to be followed, however, particularly in low-resource settings. To address this issue, a set of guideline-related documents were created to identify key priorities for users in these settings. The documents highlight the related recommendations and describe key strategies for clinicians to approach implementation of these recommendations or discuss alternatives which are in line with the intention of the recommendations, if not having all of the same advantages. The suggestions cannot be used as exact substitutes for the original recommendations in the guidelines, which have not been altered and continue to reflect best practice. This document on key priorities for low-resource settings was developed by the task force chairs and other members of the task force who produced the 2023 ESC Guidelines for the management of endocarditis, which are freely available on the ESC website (https://www.escardio.org/Guidelines). This document also underwent external review including international experts from within and beyond Europe and ESC partner organizations, including the Interamerican Society of Cardiology (IASC), The Pan-African Society of Cardiology (PASCAR), the Asian Pacific Society of Cardiology and the ASEAN Federation of Cardiology
Tensile test of wrought iron ties.
No full textSpecimens were tested on Zwick Röll Z600E according to method A1 with strain
rate control, based on the feedback obtained from the extensometer in the range up to yielding
(recommended strain rate 0,00025 s-1 was applied). In the yielding range, the strain rate control over the
parallel length (Lc =130 mm) achieved by controlling the crosshead separation rate was used (strain rate
equal to 0,00025 s-1 was applied), while after the yielding phase the strain rate was increased to 0,0067
s-1 (crosshead separation rate). Grip to grip length was 334 mm.Experimental tensile tests of wrought iron ties
How do community pharmacists perceive practice-based research?
No full textObjectives Practice-based research (PBR) is an integral part of community pharmacy practice. The results obtained from PBR allow community pharmacists to gain the knowledge necessary to develop new patient services and acquire strategies to strengthen their role in the health system. The study aimed to assess pharmacists' attitudes and barriers towards PBR and investigate the factors that prevent or motivate community pharmacists from participating.Methods The cross-sectional study was conducted in May to Jun 2023 via an online structured pretested questionnaire. All licensed pharmacists registered in the Registry of Pharmacists of the Croatian Pharmaceutical Chamber, who listed community pharmacy as a place of work participated, i.e. 500 community pharmacists. The questionnaire consisted of two sections. Section A collected the respondents' sociodemographic characteristics. Section B contained two groups of relevant statements on a 5-point Likert scale divided into two sections: pharmacists' attitudes towards research in PBRs and barriers to participation in PBRs.Key findings The results showed that 97% of community pharmacists considered PBR important for developing new pharmacy services, and almost two-thirds considered participation in research to be part of pharmacy practice. The most often perceived barrier to research participation was the workload of daily tasks necessary for normal pharmacy functioning, recognized by 68% of community pharmacists.Conclusion This study revealed community pharmacists' perception of the importance of PBR for the pharmacy profession. Involvement in PBR was important for the community pharmacists. The motivation for the PBR was present, despite the detected barriers. The results indicate the directions the community pharmacists should inspire
Energy efficiency of propulsion systems in LNG ships
No full textRad će obuhvatiti i opisati najnovije trendove u pomorskoj industriji usmjerene na smanjenje emisija stakleničkih plinova s brodova, što je postalo ključno pitanje u kontekstu globalnih napora za očuvanje okoliša i borbe protiv klimatskih promjena. Poseban naglasak biti će stavljen na sve širu primjenu prirodnog plina u pomorskom prometu, koji se više ne koristi isključivo na brodovima namijenjenima prijevozu ukapljenog prirodnog plina, već i na drugim vrstama brodova, poput tankera za prijevoz sirove nafte, brodova za prijevoz rasutog tereta, kontejnera i slično. Uporaba prirodnog plina značajno smanjuje emisije ugljikovog dioksida (CO₂) i dušikovih oksida (NOₓ), dok su emisije sumporovih oksida (SOₓ) gotovo neznatne, čime se postiže pozitivan utjecaj na okoliš i ispunjavaju stroži ekološki standardi.
Glavni dio rada biti će usmjeren na detaljnu usporedbu različitih vrsta brodskih propulzijskih sustava s obzirom na njihove performanse i razinu emisija. Analizirati će se brodovi s novim i postojećim tehnologijama za prijevoz ukapljenog prirodnog plina, uz fokus na identificiranje trenutno učinkovitije propulzijske tehnologije s aspekta emisija CO₂ i energetske učinkovitosti. U obzir će biti uzete različite vrste propulzija, uključujući: parno-turbinske sustave, DFDE sustave, dvotaktne sustave poput „ME-GI“ i „X-DF“ te dvotaktne sustave bez izgaranja plinskog goriva. Također, analizirati će se „Sayaringo STaGE“ propulzija.
Usporedba ovih tehnologija temeljiti će se na pokazateljima, uključujući pokazatelje učinkovitosti novih i postojećih brodova (EEDI i EEXI), operativni indikator energetske učinkovitosti (EEOI) na razinama opterećenja propulzije od 80 do 100%, te godišnji indikator intenziteta ugljika (CII). Uz tehničke analize, rad će opisati i relevantne inicijative i regulative Međunarodne pomorske organizacije (IMO) i Europske unije koje se odnose na smanjenje emisija u pomorskom sektoru, smanjenja intenziteta ugljika u operacijama samih brodova te implementaciju novih tehnologija.
Uz tehničke aspekte, rad će također pružiti uvid u mjere i strategije koje brodski operateri i posada mogu implementirati kako bi dodatno smanjili emisije ugljika tijekom svakodnevnih operacija. Biti će prikazani praktični primjeri, poput optimizacije rute, prilagodbe brzine plovidbe, smanjenja potrošnje goriva, itd. Na temelju provedenih analiza i usporedbi, donijet će se zaključci o najperspektivnijim tehnologijama i praksama koje mogu pridonijeti održivijem razvoju pomorskog sektora.The paper will cover and describe the latest trends in the maritime industry aimed at reducing greenhouse gas emissions from ships, which has become a key issue in the context of global efforts to protect the environment and combat climate change. Special emphasis will be placed on the increasing use of natural gas in maritime transport, which is no longer used exclusively on ships designed for transporting liquefied natural gas but also on other types of vessels, such as crude oil tankers, bulk carriers, container ships, and others. The use of natural gas significantly reduces carbon dioxide (CO₂) and nitrogen oxide (NOₓ) emissions, while sulfur oxide (SOₓ) emissions are almost negligible, resulting in a positive environmental impact and compliance with stricter ecological standards.
The main part of the paper will focus on a detailed comparison of different types of ship propulsion systems in terms of their performance and emission levels. An analysis will be conducted on ships equipped with both new and existing technologies for liquefied natural gas transportation, with a focus on identifying the most efficient propulsion technology currently available in terms of CO₂ emissions and energy efficiency. Various types of propulsion systems will be considered, including steam turbine systems, DFDE systems, two-stroke systems such as „ME-GI“ and „X-DF“, as well as two-stroke systems without gas fuel combustion. Additionally, the „Sayaringo STaGE“ propulsion system will be analyzed.
The comparison of these technologies will be based on indexes such as the efficiency index of new and existing ships (EEDI and EEXI), the operational energy efficiency indicator (EEOI) at propulsion load levels ranging from 80% to 100%, and the annual carbon intensity indicator (CII). In addition to technical analyses, the paper will also describe relevant initiatives and regulations by the International Maritime Organization (IMO) and the European Union concerning emission reduction in the maritime sector, carbon intensity reduction in ship operations, and the implementation of new technologies.
Beyond the technical aspects, the paper will also provide insights into measures and strategies that ship operators and crews can implement to further reduce carbon emissions during daily operations. Practical examples will be presented, such as route optimization, speed adjustment, and fuel consumption reduction. Based on the conducted analyses and comparisons, conclusions will be drawn on the most promising technologies and practices that can contribute to the sustainable development of the maritime sector
Oestrogenic and androgenic activity of oxybenzone and methylparaben in vitro
No full textMotivated by emerging concerns about health hazards associated with various industrial chemicals, this study investigated the disruption of endocrine system using well established in vitro assays. Due to the lack of scientific data on adverse effects of chemicals used in personal care products (PCPs), the focus was placed on oestrogenic and androgenic action of photostabiliser oxybenzone and preservative methylparaben. To this end we relied on in vitro assays for oestrogen and androgen receptor activation based on HeLa-9903 and AREcoScreen GR KO M1 cell lines to determine dose response according to respective OECD Test Guidelines 455 and 458. Our findings clearly demonstrate that both chemicals act as oestrogen receptor agonists and androgen receptor antagonists, raising additional concerns about health risks for humans posed by excessive and widespread use of such chemicals in PCPs