Electric resistivity of organic conductor K-(BEDT-TTF)2Cu2(CN)3

U ovom radu su proučavana svojstva električne otpornosti u temperaturnom rasponu od ~300K (sobne temperature) do ~20K (do kuda je dostupna aparatura davala pouzdane rezultate), organskog kristala κ-(BEDT-TTF)2Cu2(CN)3. Na temelju provedenih mjerenja ispitana su slaganja rezultata mjerenja s teorijom, odnosno s Arrheniusovim zakonom i teorijom preskoka promjenjivog dosega. U metodičkom dijelu rada predstavljen je jedan način kako bi se mogao održati istraživački tip nastave na temu električnog otpora u srednoj školi sa četverogodišnjim programom fizike.The subject of this study is electric resistivity in temperature range from ~300K (room temperature) to ~20K (temperature at which available apparatus was giving reliable results), organic crystal κ-(BEDT-TTF)2Cu2(CN)3. The study examines connection between measured results and the theory, respectively with Arrhenius law and theory of variable range hopping. Educational part shows an exploratory teaching method how to present electric resistance in high school within four year program of physics

The impact of disrupted monoamine homeostasis on lipid metabolism, activity of monoamine oxidase type b and serotonin concentration in platelets

Poremećaj središnje homeostaze monoamina, kao podloga različitih psihijatrijskih poremećaja, pa tako i poremećaja ličnosti i suicidalnog ponašanja, utječe na metabolizam lipida i aktivnost monoaminooksidaze tipa B (MAO-B) i koncentraciju serotonina (5-HT) u trombocitima. Cilj istraživanja je bio odrediti utjecaj promijenjene homeostaze središnjih monoamina na metabolizam lipida te aktivnost MAO-B i koncentraciju 5-HT u trombocitima bolesnica s poremećajem ličnosti sa i bez suicidalnog ponašanja te ih usporediti s vrijednostima izmjerenim u zdravim kontrolnim ispitanicama. Metode: Lipidne frakcije i trombocitni pokazatelji određeni su u uzorcima krvi ispitanica laboratorijskim i spektrofluorimetrijskim metodama. Rezultati su obrađeni pomoću analiza varijance, Tukeyovog testa, Student t-testa, regresijske analize i Spearmanovog koeficijenta korelacije. Rezultati: Koncentracija ukupnog kolesterola značajno je snižena u suicidalnih bolesnica u odnosu na kontrolne ispitanice, koncentracija trombocitnog 5-HT i LDL-a značajno je snižena u suicidalnih i nesuicidalnih bolesnica u odnosu na kontrolnu skupinu, a koncentracija triglicerida značajno je povišena kod nesuicidalnih bolesnica u odnosu na kontrolnu skupinu. Trombocitni 5-HT bio je značajno povezan s kolesterolom i LDL-kolesterolom. Zaključak: Koncentracije trombocitnog 5-HT i LDL-kolesterola mogle bi poslužiti kao indikatori poremećaja ličnosti, dok je koncentracija ukupnog kolesterola jedini periferni pokazatelj koji razlikuje suicidalne i nesuicidalne ispitanice te bi mogao poslužiti kao potencijalni marker suicidalnosti. Rezultati upućuju da je smanjena periferna monoaminska funkcija, povezana s kolesterolom, karakteristična značajka poremećaja ličnosti.The disruption of central monoamine homeostasis, as the basis of personality disorders and suicidal behaviour, affects lipid metabolism and monoamine oxidase type B (MAO-B) activity and serotonin (5-HT) concentration in platelets. Aim was to determine the influence of this altered homeostasis on lipid and platelet markers in female personality disorder patients with and without suicidal behaviour and to compare these markers with values in healthy control women. Methods: Lipid fractions and platelet markers were determined in blood samples of subjects with standard laboratory and spectrofluorimetric methods. Results were evaluated with analysis of variance, Tukey test, Student t-test, regression analysis and Spearman coefficient of correlation. Results: Serum total cholesterol was significantly lower in suicidal patients compared to control subjects, concentration of platelet 5-HT and LDL-cholesterol was significantly lower in suicidal and nonsuicidal patients compared to controls, and concentration of triglycerides was significantly higher in nonsuicidal patients compared to controls. Platelet 5-HT was significantly positively correlated with cholesterol and LDL-cholesterol. Conclusion: The concentration of platelet 5-HT and LDL cholesterol could serve as indicators of personality disorders, while serum total cholesterol, which is the only peripheral indicator that distinguishes suicidal and nonsuicidal patients, could serve as a potential indicator of suicididality. The results suggest that the reduced peripheral monoamine function, associated with cholesterol, is a characteristic feature of personality disorders

Monitoring of omeprazole synthesis by hyphenated LC-SPE/NMR system. NMR and high-school chemical syllabus.

U ovom diplomskom radu opisano je praćenje reakcije oksidacije omeprazol sulfida, poslijednjeg koraka prilikom sinteze omeprazola, pomoću spregnutog sustava tekućinska kromatografija-ekstrakcija na čvrstoj fazi-nuklearna magnetska rezonancija (LC-SPE/NMR). Omeprazol je lijek koji se koristi za liječenje bolesti uzrokovane pretjeranim lučenjem želučane kiseline, a djeluje tako da regulira enzimski sustav odgovoran za njezino izlučivanje. U radu su optimirani uvjeti tekućinskokromatografskog odjeljivanja, skladištenja uzoraka na sustavu SPE te snimanja spektara NMR. Uspoređene su metodologije on-line i off-line za praćenje sinteze omeprazola i identifikaciju produkata, nusprodukata i nečistoća. U okviru metodičkog dijela rada prikazan je prijedlog nastavnog sata pod nazivom „Nuklearna magnetska rezonancija“ u kojem je opisana priprema sata namijenjena učenicima četvrtog razreda srednje škole te je detaljno razrađen radni listić za učenike.This thesis describes monitoring the oxidation reaction of omeprazole sulfide, which is the last step in omeprazole synthesis by hyphenated liquid chromatography-solid phase extraction-nuclear magnetic resonance methodology (LC-SPE/NMR). Drug Omeprazole blocks enzyme system responsible for the secretion of gastric acid. That is the reason why it is used for the treatment of diseases caused by hypersecretion of gastric acid. Conditions of liquid chromatography separation, trapping on SPE cartridges and recording of NMR spectra were optimized. On-line and off-line methodologies for monitoring the omeprazole synthesis and identification of products, byproducts and impurities were disscused. In the second part of this thesis one of the possible modern approaches in teaching chemistry for high school students have been elaborated. The title of the topic is „Nuclear magnetic resonance“ and a worksheet for students is enclosed

Early Representational Gestures across Bantu and Romance Languages: A Matter of Age or a Matter of Language & Culture?

National audienc