Obnovljivi izvori energije u kontekstu morske tehnologije – sadašnjost i budući trendovi

Energija mora kao jedan od najmanje iskorištenih obnovljivih izvora energije zahtjeva više pažnje u znanstvenom i stručnom smislu. Ovaj rad daje sažeti pregled potencijala energije mora, te različitih vrsta i principa rada različitih uređaja za iskorištavanje energije valova u kojoj je sadržana najveća količina neiskorištenog potencijala energije mora

Dependence of changes in pressure of superheated steam for reducing heat drop in the throttling regulation of steam turbines

Regulation of the steam turbine can be achieved by optimal, reliable and safe operation. Power regulation adjusts the operation of the steam turbine load current, i.e., it changes the thermal drop (throttling control) or quantity of steam (nozzle control group). An analysis of the throttling regulation reveals the turbine power dependence on the pressure and the supplied amount of steam, and shows the losses due to a pressure drop in the aforementioned regulation

Solarna energija u priobalnom području Republike Hrvatske – danas i sutra

Ovaj rad daje sažeti pregled korištenja solarne energije u RH poglavito u priobalnom području. Izneseno je sadašnje stanje eksploatacije solarne energije, te buduće projekcije korištenja ovog obnovljivog izvora energije

Systemic lupus erythematosus in pregnancy

Sistemni eitematozni lupus (SLE) je autoimuna bolest od koje poglavito obolijevaju žene reprodukcijske dobi. Trudnoća i njen ishod glavna su briga za većinu pacijenata. Rizik za egzacerbacijom bolesti u trudnoći i rizik gubitka ploda te prijevremenog poroda su viši, te je i povećana potreba za sigurnijim liječenjem. S napretkom razumijevanja patogeneze sistemnog eritematoznog lupusa i nužnosti upotrebe imunosupresivne terapije može se postići dobra kontrola bolesti i pacijentima je danas omogućena prilika da začnu i imaju djecu. Savjetovanje o trudnoći i uska suradnja s drugim specijalistima kao što su ginekolozi i reumatolozi ključna je za idealan ishod i majke i djeteta u trudnoći. U ovom radu raspravljene su važne teme poput planiranja trudnoće, kontracepcije, egzacerbacije bolesti u trudnoći i komplikacija, te ishod trudnoće. Isto tako prikazan je i sustavni plan praćenja takve trudnoće kao i pregled lijekova koji se danas koriste, te teme koje su usko povezane sa samom trudnoćom kao što su laktacija i neonatalni lupus.Systemic lupus erythematosus (SLE) is an autoimmune disease that primarily affects women of reproductive age. Pregnancy and its outcome are the main concern for most patients. The risk of exacerbation of the disease during pregnancy and the risk of miscarriage and premature birth are higher, and the increased need for safer treatment. With the advancement of the understanding of the pathogenesis of systemic lupus erythematosus and the necessity of the use of immunosuppressive therapy can be achieved by good control of the disease and the patient is now provided an opportunity to conceive and have children. Advice on pregnancy and close cooperation with other specialists such as gynecologists and rheumatologists is essential for the ideal outcome of both mother and child during pregnancy. In this review, I have also discussed the important issues such as planning pregnancy, contraception, exacerbations of the disease in pregnancy, pregnancy complications and the outcome of pregnancy. Also shown is the systematic monitoring plan such as pregnancy and review of medicines used today, topics that are closely related to the pregnancy, such as lactation and neonatal lupus

Systemic lupus erythematosus in pregnancy

Sistemni eitematozni lupus (SLE) je autoimuna bolest od koje poglavito obolijevaju žene reprodukcijske dobi. Trudnoća i njen ishod glavna su briga za većinu pacijenata. Rizik za egzacerbacijom bolesti u trudnoći i rizik gubitka ploda te prijevremenog poroda su viši, te je i povećana potreba za sigurnijim liječenjem. S napretkom razumijevanja patogeneze sistemnog eritematoznog lupusa i nužnosti upotrebe imunosupresivne terapije može se postići dobra kontrola bolesti i pacijentima je danas omogućena prilika da začnu i imaju djecu. Savjetovanje o trudnoći i uska suradnja s drugim specijalistima kao što su ginekolozi i reumatolozi ključna je za idealan ishod i majke i djeteta u trudnoći. U ovom radu raspravljene su važne teme poput planiranja trudnoće, kontracepcije, egzacerbacije bolesti u trudnoći i komplikacija, te ishod trudnoće. Isto tako prikazan je i sustavni plan praćenja takve trudnoće kao i pregled lijekova koji se danas koriste, te teme koje su usko povezane sa samom trudnoćom kao što su laktacija i neonatalni lupus.Systemic lupus erythematosus (SLE) is an autoimmune disease that primarily affects women of reproductive age. Pregnancy and its outcome are the main concern for most patients. The risk of exacerbation of the disease during pregnancy and the risk of miscarriage and premature birth are higher, and the increased need for safer treatment. With the advancement of the understanding of the pathogenesis of systemic lupus erythematosus and the necessity of the use of immunosuppressive therapy can be achieved by good control of the disease and the patient is now provided an opportunity to conceive and have children. Advice on pregnancy and close cooperation with other specialists such as gynecologists and rheumatologists is essential for the ideal outcome of both mother and child during pregnancy. In this review, I have also discussed the important issues such as planning pregnancy, contraception, exacerbations of the disease in pregnancy, pregnancy complications and the outcome of pregnancy. Also shown is the systematic monitoring plan such as pregnancy and review of medicines used today, topics that are closely related to the pregnancy, such as lactation and neonatal lupus

Friction compensation in ultrahigh-precision positioning

Ultrahigh -precision positioning devices are essential in precision engineering and microsystems’ technologies. As they need to allow sub- micrometric or even nanometric displacements, their nonlinear frictional behaviour, induced by a number of sliding and rolling components, has to be efficiently compensated for. If a model-based approach is followed, suitable modelling of such disturbances, which is generally performed using state-of the art friction models, has to be performed. An overview of different compensation and control algorithms applied to ultrahigh-precision positioning systems is hence given in this work

Characterization of influential parameters on friction in the nanometric domain using experimental and machine learning methods

Friction is a ubiquitous phenomenon of great research interest in engineering practice. Fundamental frictional features of two solids in contact and in relative motion are governed by microscopic single asperity contacts at their interface. A structured multidisciplinary approach to the experimental determination of friction in the nanometric domain is presented in this work. The dependence of nanoscale friction on process parameters comprising the materials in relative motion, normal forces, sliding velocities and the temperature conditions is studied experimentally by employing scanning probe microscopy. The data hence attained from multidimensional experimental measurements on thin-film samples is used for the development of machine learning-based models. In fact, due to the stochastic nature of the considered phenomena, conventional regression methods yield poor predictive performances, prompting thus the usage of the machine learning numerical paradigm. Such an approach enables obtaining an insight into the concurrent influence of the process parameters on nanoscale friction. A comparative study allows thus showing that, while the best typical regression models result in coefficients of determination (R2) of the order of 0.3, the predictive performances of the used machine learning models, depending on the considered sample, yield R2 in the range from 0.54 to 0.9. The proposed method, aimed at accomplishing an in-depth insight into the physical phenomena influencing nanoscale frictional interactions, will be complemented next with advanced studies based on genetic programming-based artificial intelligence methods. These could, in fact, allow obtaining a functional description of the dependence of nanoscale friction on the studied variable parameters, thus enabling not only true nanoscale friction prediction but also an important tool for control purposes

sequence, conformation, stereochemistry, self-assembly or their interplay?

Funding Information: This work utilized resources of the Bura supercomputer facility at the University of Rijeka, Center for Advanced Computing and Modeling. This work was supported by the Croatian Science Foundation [grant numbers UIP-2019-04-7999, DOK-2021-02-3496] and the University of Rijeka [grant number uniri-mladi-intpo-22-32790]. Publisher Copyright: © 2023 The Royal Society of Chemistry.The sequence-to-function relationship of peptide-based catalysts remains a challenge, as even subtle modifications at the sequence level can alternate their catalytic activity. A set of linear and cyclic histidine-rich peptides was synthesized to assess the impact of amino acid disposition, cyclization, and incorporation of d-amino acids on their ability to self-assemble, coordinate Zn2+ ions, and show intrinsic hydrolase-like activity. Self-assembly into β-sheets was confirmed for both linear peptides and one cyclic analogue (cy-hh) by FTIR, ThT binding, CD, and AFM. Interestingly, only peptide A demonstrated efficient ester hydrolysis of p-NPA, p-NPB and p-NPO substrates, indicative of its effective Zn2+ coordination. Our findings highlight that increased rigidity of the peptide can hinder metal ion coordination by limiting the necessary conformational adjustments for optimal Zn2+ binding. These insights into the structural changes underlying the function of short peptides offer valuable knowledge for the design of metal-dependent peptide-based catalysts.publishersversionpublishe