A survey of recent experimental and theoretical results in non-linear optics

Tema ovog završnog rada je detaljan pregled novijih rezultata u nelinearnoj optici. Kako bi se bolje opisala tema svjetlosti, opisani su i objašnjeni elektromagnetski valovi te odgovarajuće Maxwellove jednadžbe. Nelinearna optika bavi se istraživanjem nelinearnog odziva materijala poput nelinearnih kristala na intenzitet optičkog polja. Ovaj rad se koncentrira uglavnom na nelinearne optičke procese, poput udvostručenja frekvencija, dobivanja drugog i trećeg harmonika te dobivanja zbroja i razlika frekvencija. Opisani su kristali i materijali koji su najčešće odgovorni za takve efekte. Spomenuti su optički solitoni, metode polarizacije svjetlosnih valova, zajedno s Ramanovim i Brillouinovim raspršenjem. Široka primjena ovih efekata varira od informacijskih tehnologija i brzog prijenosa podataka preko optičkih vlakana, do pojačanja svjetlosti laserskih izvora te raznih nelinearnih detektora. Značajnost ovih teorijskih i eksperimentalnih rezultata leži upravo u primjeni neočekivanog ponašanja svjetlosti visokog intenziteta i koherencije.The subject of this final thesis is a detailed review of recent results regarding non-linear optics in the field of physics. In order to better understand the subject of light, elecromagnetic waves were described and explained, along with corresponding Maxwell's equations. Non-linear optics focuses on the response of optical materials such as non-linear crystals (NLC) to optical field intensity. The thesis is mainly concerned with non-linear optical processes, such as frequency doubling, second and third harmonic generation, sum- and difference frequency generation. The nanocrystals responsible for non-linear effects were thoroughly explained. Optical solitons and wavepolarization methods were mentioned, among Raman and Brillouin scattering. It was found that a wide array of applications is possible within these effects, ranging from information technologies and high-speed data transfer via optical fiber, to laser light amplification and various non-linear detectors. The significance of these findings lies within the application of unexpected light behavior at high intensity and coherence rates

A survey of recent experimental and theoretical results in non-linear optics

Tema ovog završnog rada je detaljan pregled novijih rezultata u nelinearnoj optici. Kako bi se bolje opisala tema svjetlosti, opisani su i objašnjeni elektromagnetski valovi te odgovarajuće Maxwellove jednadžbe. Nelinearna optika bavi se istraživanjem nelinearnog odziva materijala poput nelinearnih kristala na intenzitet optičkog polja. Ovaj rad se koncentrira uglavnom na nelinearne optičke procese, poput udvostručenja frekvencija, dobivanja drugog i trećeg harmonika te dobivanja zbroja i razlika frekvencija. Opisani su kristali i materijali koji su najčešće odgovorni za takve efekte. Spomenuti su optički solitoni, metode polarizacije svjetlosnih valova, zajedno s Ramanovim i Brillouinovim raspršenjem. Široka primjena ovih efekata varira od informacijskih tehnologija i brzog prijenosa podataka preko optičkih vlakana, do pojačanja svjetlosti laserskih izvora te raznih nelinearnih detektora. Značajnost ovih teorijskih i eksperimentalnih rezultata leži upravo u primjeni neočekivanog ponašanja svjetlosti visokog intenziteta i koherencije.The subject of this final thesis is a detailed review of recent results regarding non-linear optics in the field of physics. In order to better understand the subject of light, elecromagnetic waves were described and explained, along with corresponding Maxwell's equations. Non-linear optics focuses on the response of optical materials such as non-linear crystals (NLC) to optical field intensity. The thesis is mainly concerned with non-linear optical processes, such as frequency doubling, second and third harmonic generation, sum- and difference frequency generation. The nanocrystals responsible for non-linear effects were thoroughly explained. Optical solitons and wavepolarization methods were mentioned, among Raman and Brillouin scattering. It was found that a wide array of applications is possible within these effects, ranging from information technologies and high-speed data transfer via optical fiber, to laser light amplification and various non-linear detectors. The significance of these findings lies within the application of unexpected light behavior at high intensity and coherence rates

Analysis of lymphocyte glucocorticoid receptor phosphorylation in healty subjets and patients with current episode of depressive disorder

Depresivni poremećaj (DP) je multifaktorijalno oboljenje, široko rasprostranjeno u svetu, i rasvetljavanje mehanizama koji su u osnovi ovog poremećaja predstavlja jedan od najvećih izazova biomedicinskih istraţivanja današnjice. Narušena funkcija hipotalamo-hipofizno-adrenalne (HHA) ose, kao i signalizacija preko glukokortikoidnog receptora (GR), čest su nalaz kod pacijenata sa DP-om. Takođe, određeni stepen disfunkcije HHA ose i samog GR-a uočavaju se i kod zdravih ljudi i pretpostavlja se da to predstavlja jedan od faktora rizika za razvoj kliničke depresije. S druge strane, uspešno lečenje pacijenata sa depresijom, praćeno je normalizacijom aktivnosti HHA ose i funkcije GR-a. GR je ligand-zavisan transkripcioni faktor, koji nakon vezivanja glukokortikoida (krajnjih produkata aktivnosti HHA ose) prelazi iz citoplazme u jedro gde reguliše ekspresiju velikog broja gena. Vaţan način regulacije funkcije GR-a postiţe se njegovom fosforilacijom koja je posredovana aktivnošću kinaza, koje se aktiviraju u odgovoru na različite ćelijske signale. Fosforilacija GR-a na serinu 211 (S211) stimuliše ulazak receptora u jedro i generalno se smatra biomarkerom njegove povećane transkripcione aktivnosti, dok je za fosforilaciju GR-a na serinu 226 (S226), koja je posredovana c-Jun N-terminalnim kinazama (eng. c-Jun N-terminal kinases, JNK), pokazano da inhibira njegovu transkripcionu aktivnost i stimuliše izlazak GR-a iz jedra u citoplazmu. Među genima stimulisanim glukokortikoidima su GILZ (eng. glucocorticoid-induced leucine zipper, GILZ), vaţan posrednik anti-inflamatornih efekata GR-a, i FKBP5 (eng. FK506 binding protein 5, FKBP5), koji ima vaţnu ulogu u ograničavanju glukokortikoidne signalizacije u ćeliji, sprečavajući translokaciju GR-a iz citoplazme u jedro...Major depressive disorder (MDD) is a multifactorial illness that a ffects people across the globe and u derstanding mechanisms underlying this disorder represents a major challenge of biomedical research today. One of the most consistent findings among patients with MDD is dysfunctional hypothalamic – pituitary – adrenal (HPA) axis, caused by altered function of the glucocorticoid receptor (GR). In healthy population, individuals with impaired HPA axis and GR function are also observed, and these features are believed to represent increased risk factors for depression . On the o ther hand, successful antidepressant treatments ameliorate many of the neuroendocrine disturbances observed in depression . The GR is ligand - activated transcriptional factor that apon glucocorticoid binding (glucocorticoids are end products of HPA axis acti vity) translocate from the cytoplasm to the nucleus where it modulates the expression of wide variety of genes. Phoshor y lation of the GR, mediated by activity of diverse cellular kinases, is imprtant way of regulating GR function. The GR phosphorylation at S211 promotes GR translocation to the nucleus and enhances its transcriptional activity , while GR phosphorylation at S226, mediated by c - Jun N - terminal kinases (JNK), inhibits its transcriptional activity and promotes GR nuclear export. Some of m yriad of genes whose expression is stimu late d by the GR are glucocorticoid - induced leucine zipper (GILZ), an important mediator of glucocorticoid anti - imflamatory actions, and FK506 binding protein 5 (FKBP5), which is a part of an intracellular ultra - short negative feedback loop for GR activity..

Tryptophan metabolites in depression: Modulation by gut microbiota

Clinical depression is a multifactorial disorder and one of the leading causes of disability worldwide. The alterations in tryptophan metabolism such as changes in the levels of serotonin, kynurenine, and kynurenine acid have been implicated in the etiology of depression for more than 50 years. In recent years, accumulated evidence has revealed that gut microbial communities, besides being essential players in various aspects of host physiology and brain functioning are also implicated in the etiology of depression, particularly through modulation of tryptophan metabolism. Therefore, the aim of this review is to summarize the evidence of the role of gut bacteria in disturbed tryptophan metabolism in depression. We summed up the effects of microbiota on serotonin, kynurenine, and indole pathway of tryptophan conversion relevant for understanding the pathogenesis of depressive behavior. Moreover, we reviewed data regarding the therapeutic effects of probiotics, particularly through the regulation of tryptophan metabolites. Taken together, these findings can open new possibilities for further improvement of treatments for depression based on the microbiota-mediated modulation of the tryptophan pathway

Mechanochemically Induced Anion Exchange in Aminoazobenzene Salts

Aminoazobenzene sulfate salt reacts with the crystals of KBr in solid-state under high pressure yield-ing corresponding bromide salt. The reactant and product differ also in the position of protonation, amino group, and azo group, respectively. Since protonation of azo-group destroys the coplanarity of two benzene rings and diminishes -conjugation, the product differs from the reactant also in color, from orange to violet. Hence, the reaction is the example of the piezochromic effect. This solid-state process is studied by kinetic measurements, and the structures of the compounds were analyzed by X-ray chrystallography

Test results comparison and sample stability study: is the BD Barricor tube a suitable replacement for the BD RST tube?

Introduction: The aim was to evaluate the BD Barricor tubes by comparison with the BD Rapid Serum Tubes (RST) through measuring 25 analytes and monitoring sample stability after 24 hours and 7 days. Materials and methods: Samples of 52 patients from different hospital departments were examined. Blood was collected in BD RST and BD Barricor tubes (Becton, Dickinson and Company, Franklin Lakes, USA). Analytes were measured by Beckman Coulter AU 480 (Beckman Coulter, Brea, USA), Dimension EXL (Siemens Healthcare Diagnostics, Newark, USA) and ARCHITECT i2000SR (Abbott Diagnostics, Lake Forest, USA). Between-tube comparison for each analyte was performed, along with testing analyte stability after storing samples at 4 °C. Results: BD Barricor tubes showed unacceptable bias compared to BD RST tubes for potassium (K) (- 4.5%) and total protein (4.4%). Analyte stability after 24 hours was acceptable in both tested tubes for most of analytes, except for glucose, aspartate aminotransferase (AST) and lactate dehydrogenase (LD) in BD Barricor and free triiodothyronine in BD RST sample tubes. Analyte stability after 7 days was unacceptable for sodium, K, calcium, creatine kinase isoenzyme MB, AST, LD and troponin I in both samples; additionally for glucose, alkaline phosphatase and albumin in BD Barricor. Conclusion: All analytes, except K and total protein, can be measured interchangeably in BD RST and BD Barricor tubes, applying the same reference intervals. For most of the analytes, sample re-analysis can be performed in both tubes after 24 hours and 7 days, although BD RST tubes show better 7-day analytes stability over BD Barricor tubes

Verification of the Automated ELISA Assay for Hepcidin-25 in Human Serum

Introduction: Hepcidin-25, the bioactive form of hepcidin, is the master protein in regulating iron homeostasis. Serum concentrations, measured by different methods, are often incomparable and complicate results interpretation. Materials and Methods: The aim was to verify the first fully automated enzyme-linked immunosorbent assay (ELISA) method, using the DRG Hybrid XL analyzer (DRG Instruments, Marburg, Germany) standardized against the mass spectrometry method. Intra- (CVi) and inter-assay (CVg) precision and bias were performed using commercially available controls with low (C1) and high (C2) concentrations. The reference interval was verified by analyzing serum samples of 20 healthy males. Results: CVi = 9.1% (C1), 4.5% (C2); CVg = 8.9% (C1), 5.6% (C2); calculated bias was 33% for C1 and 20% for C2, respectively. Conclusion: Verification of the fully automated ELISA method for hepcidin-25 in serum on the DRG Hybrid XL analyzer met the analytical acceptance criteria

Utjecaj traheotomije na klinički tijek ventilacijske pneumonije

Ventilator-associated pneumonia (VAP) is the most common infection among intensive care unit (ICU) patients. The aim of the present study was to evaluate the impact of tracheotomy on VAP clinical course. The study was conducted in a 15-bed Surgical and Neurosurgical ICU, Department of Anesthesiology and Intensive Care, Sestre milosrdnice University Hospital Center in Zagreb, Croatia. All patients developing VAP during ICU stay were eligible for the study. In VAP patients not tracheotomized during ICU stay, the mortality rate was approximately two times higher as compared with patients tracheotomized either before or after VAP onset (crude risk ratio 1.83, 95% confidence interval (95% CI) 1.15-2.91, p=0.01; crude odds ratio 3.47, 95% CI 1.52-7.94; p=0.003). In the surviving VAP patients, the duration of mechanical ventilation before VAP onset was higher in the “T before VAP” group as compared with the “no T before VAP” group (8, 6-10 vs. 3, 2-5; p<0.001), but the number of post-VAP days on mechanical ventilation was shorter in “T before VAP” patients than in “no T before VAP” patients (0, 0-1 vs. 4, 3-9; p<0.001). The duration of mechanical ventilation after VAP onset in the “T after VAP” group was longer as compared with the “T before VAP” group (4, 3-12 vs. 0, 0-1; p<0.001). The present study indicated tracheotomy to be associated with a reduced duration of mechanical ventilation after VAP onset, but only if patients were tracheotomized at the moment of VAP onset.Ventilacijska pneumonija (ventilator-associated pneumonia, VAP) je jedna od najčešćih infekcija među bolesnicima u jedinicama intenzivnog liječenja (JIL). Cilj ovoga istraživanja je bio utvrditi utjecaj traheotomije na klinički tijek VAP-a. Istraživanje je provedeno u 15-krevetnoj Jedinici intenzivnog liječenja Odjela za anesteziologiju, reanimatologiju i intenzivno liječenje u Kliničkom bolničkom centru “Sestre milosrdnice”, Zagreb, Hrvatska. Svi bolesnici u kojih se razvila VAP tijekom navedenog razdoblja bili su uključeni u istraživanje. U bolesnika s VAP koji nisu traheotomirani (T) tijekom njihovog boravka u JIL-u smrtnost je bila otprilike dva puta veća u usporedbi s bolesnicima koji su traheotomirani prije ili nakon razvoja VAP (crude risk ratio 1,83, 95% confidence interval (CI) 1,15-2,91, p=0,01; crude odds ratio 3,47, 95% CI 1,52-7,94; p=0,003). Među preživjelim bolesnicima trajanje mehaničke ventilacije prije razvoja VAP je bilo duže u skupini “T prije VAP” u usporedbi sa skupinom “bez T prije VAP” (8, 6-10 prema 3, 2-5; p<0,001), ali je broj dana mehaničke ventilacije nakon razvoja VAP bio kraći u bolesnika skupine “T prije VAP” u usporedbi s onima skupine “bez T prije VAP” (0, 0-1 prema 4, 3-9; p<0,001). Trajanje mehaničke ventilacije nakon razvoja VAP u skupini “T nakon VAP” je bilo duže u usporedbi sa skupinom “T prije VAP” (4, 3-12 prema 0, 0-1; p<0,001). Ovo istraživanje je ukazalo na to da je traheotomija povezana s kraćim trajanjem mehaničke ventilacije nakon pojave VAP, ali samo ako su bolesnici u trenutku pojave VAP traheotomirani

Experiences of foreign-language teachers at the tertiary level in the online teaching environment in Croatia in 2020

Cilj rada bio je istražiti jesu li i na koji način prilagođene metode poučavanja, vanjske okolnosti i unutrašnji faktori nezadovoljstva nastavnika utjecali na percepciju uspješnosti online nastave stranih jezika struke na visokoškolskoj razini. U istraživanju je sudjelovalo 60 nastavnika iz 13 hrvatskih gradova, koji su u prosincu 2020. i siječnju 2021. ispunili anketni upitnik. U radu se ispituju: (i) utjecaj prilagođenih metoda poučavanja u online nastavi (kroz prilagođene nastavne materijale, način poučavanja, način vrednovanja studenata) na percipiranu uspješnost online nastave; (ii) utjecaj vanjskih faktora (onih na koje nastavnik nije mogao izravno utjecati: broj sati, veličina grupe, podrška institucije itd.) na percipiranu uspješnost online nastave; (iii) faktori nezadovoljstva nastavnika u online nastavi. Rezultati istraživanja pokazuju da su nastavnici koji su prilagodili metode poučavanja online nastavi bili zadovolj-niji uspjehom svoje online nastave, kao i njihovi studenti. Također, pokazalo se da nepovoljni vanjski faktori kao i subjektivni faktori nezadovoljstva nastavnika nisu bitno utjecali na percipiranu uspješnost online nastave. Na kraju rada donose se preporuke za daljnja istraživanja. Istraživanje pridonosi cjelokupnoj raspravi o online nastavi jezika struke na tercijarnoj razini i nudi praktične primjere za pripremu i provedbu online nastave, izradu nastavnih materijala te praćenje i vrednovanje studenata.This study endeavours to determine whether, and to what extent, adapted methods, external circumstances, and subjective factors impacted teachers’ performance in the online teaching of foreign languages for professional purposes at the tertiary level, as evaluated by the teachers themselves. a survey was carried out via an online questionnaire in December 2020 and in January 2021; the sample consisted of 60 respondents from 13 towns in Croatia. The study explored (i) the impact of adapted teaching methods in online teaching on teachers’ performance; (ii) the impact of external factors on teachers’ performance (external factors defined as those which teachers could not directly influence, such as the number of classes, the size of groups, online platforms, academic misconduct among students, working conditions, the support of higher education institutions); (iii) the factors of teacher dissatisfaction with teaching online. The results of the study reveal that the teachers who managed to adapt their teaching methods to the online medium are more satisfied with their performance, and so are their students. Furthermore, the adverse external factors, as well as subjective factors of dissatisfaction, did not substantially impact the performance of online teaching. The study contributes to the debate on the teaching of foreign languages for professional purposes at the tertiary level and offers practical implications for preparing and organising online classes, selecting teaching materials, and assessing and evaluating students. Finally, the study provides recommendations for further research on online foreign-language teaching in higher education

Impact of harvest date on the content of volatile components in garlic

The aim of this study was to define optimal harvesting date of garlic cv. \u27Istarski crveni\u27 by comparing the amount of volatile compounds as one of quality indicators. In total 17 volatile compounds were determined in tested garlic samples by headspace solid-phase microextraction coupled to gas chromatography with flame ionization and mass spectrometric detection (HS-SPME-GC-FID-MS) regardless of harvesting date. Major volatiles diallyl trisulfide, diallyl sulfide, methyl allyl disulfide and diallyl disulfide representing 98.5 % of all the determined compounds have shown no significant difference between harvest dates. Significantly higher content of the two minor volatiles, allyl mercaptane and thieno[2,3-b]thiophene, was found in the last and second when compared to the first harvest date. Principal components PC1 and PC2 explained 78% of the total variance and pointed to certain relations between harvest dates and volatiles. The technological maturity had probably been reached at the first harvesting date since similar amounts of volatiles were found during the observed period