The line graph L(G) of a graph G is defined as a graph having vertex set identical with the set of edges of G and two vertices of L(G) are adjacent if and only if the corresponding edges are incident in G. Higher iteration L i(G) is obtained by repeatedly applying the line graph operation i times. Wiener index W(G) of a graph G is defined as the sum of distances which runs over all pairs of vertices in G. The problem of establishing the extremal values and extremal graphs for the ratio W(L i(G))/W(G) was proposed by Dobrynin and Melnikov [Mathematical Chemistry Monographs, Vol. 12, 2012, pp. 85-121]. In this paper we establish the maximum value and characterize the extremal graphs for i = 1. In doing so, we derive unexpectedly an interesting relation that involves the Gutman index and the first Zagreb index.

Uvod: U današnje vrijeme kao glavni alat za procjenu starosti u forenzičkoj medicine koriste se radiološki snimci. Pojavom kompjuterizirane tomografije konusnim snopom omogućen je 3D uvid u anatomske strukture zuba, a samim tim unaprijeđen i olakšan proces identifikacije, obzirom da su zubi najtvrđi dio ljudskog tijela i kao takvi se često koriste za procjenu starosti. Cilj rada je ispitati radnu hipotezu prema kojoj dentalna dob procijenjena metodom volumetrijske analize pulpe kompjuteriziranom tomografijom konusnim snopom odgovara hronološkoj dobi ispitanika. Metode: Kroz ovu prospektivnu pilot studiju analizirani su CBCT snimci bosanskohercegovačke populacije kod 30 ispitanika (17 žena i 13 muškaraca). Snimci su u .DICOM formatu importovani u ITK Snap program pomoću kojeg je izmjeren volumen pulpe zuba interkaninog sektora gornje i donje vilice, i to za očnjake, centralne i lateralne sjekutiće. Kriteriji za uključivanje podrazumijevali su odsustvo kalcifikacije, artefakata i bez većih restauracija kod navedenih zuba. Podaci o svakom mjerenju korelirani su sa dobi i spolom ispitanika. Statistička obrada i interpretacija prikupljenih podataka urađena je pomoću statističkog programa SPSS. Rezultati: Provedeno istraživanje je potvrdilo da se volumen pulpe zuba smanjuje sa godinama starosti. Dob ispitanika je varirala između 16 i 54 godine. Najmanji volumen pulpe izmjeren je kod centralnog sjekutića mandibule, a najveći kod maksilarnog očnjaka. Volumen pulpe zuba gornje vilice općenito je bio veći nego kod zuba donje vilice. Kod žena je zabilježen manji volumen pulpe zuba u odnosu na volumen pulpe kod muškaraca. Zaključak: Kod svih analiziranih zuba postojala je značajna korelacija između dobi i volumena pulpe zuba, sa jačom korelacijom kod muškaraca. Studija je pokazala da se dob može procijeniti na osnovu poznavanja volumena pulpe zuba interkanine regije, uz uspostavljanje matematičkog modela za koji je potreban veći broj ispitanika.

Funkcionalna magnetna rezonanca (fMRI) je neinvazivna dijagnostička metoda koja služi za vizualizaciju nervne aktivnosti u ljudskom mozgu. Svoju primjenu je našla u neurologiji i omogućava bolje praćenje bolesti, njihovu klasifikaciju, prognozu i liječenje. To je sigurna i ponovljiva metoda, kako za djecu tako i za odrasle, te je svoju primjenu našla i u drugim naukama. Ovaj pregledni rad uključuje 20 naučno–istraživačkih radova, koji su u svojim rezultatima opisali tehniku izvođenja fMRI, njene prednosti i ograničenja, kao i oboljenja u kojima je našla kliničku primjenu. Primjenom fMRI u praksi počela je revolucija u polju neuroimaging-a. Umjesto da magnetna rezonanca daje samo anatomsku sliku i neke osnovne fiziološke informacije, sada je mogla da proizvodi dinamičke mape aktivacije mozga. FMRI se ne treba smatrati konkurentskom metodom, već komplementarnom, te umjesto da se koristi u svrhu pobijanja ili potvrđivanja određene dijagnoze, ona bi se mogla koristiti kao dopunska metoda za mnoge konvencionalne testove.

Uvod: Adenomi hipofize su benigni tumori prednjeg režnja hipofize i čine 10% svih intrakranijalnih tumora. Metoda izbora za njihovu evaluaciju i dijagnostiku je magnetna rezonanca. Pruža korisne informacije o odnosu hipofize sa susjednim anatomskim strukturama i temelj je dijagnoze, nadzora, planiranja medicinske ili hirurške strategije i procjene odgovora na liječenje. Metode: U ovom istraživanju uključeno je 14 randomiziranih prospektivnih i retrospektivnih studija, sistemskim odabirom na internet bazama: PubMed, Google Scholar, Crossref i Researchgate. Ispitanici su različite starosne i spolne strukture. Razmotrene su studije koje su uključivale magnetnu rezonancu hipofize i njen značaj i senzitivnost prilikom dijagnostike adneoma hipofize. Ciljevi: Utvrditi značaj magnetne rezonance u dijagnostici adenoma hipofize. Komparirati magnetnu rezonancu sa ostalim radiološkim modalitetima snimanja hipotalamo-hipofizne regije te utvrditi senzitivnost magnetne rezonance prilikom dijagnosticiranja mikroadenoma. Rezultati: Na osnovu sistemskog pregleda literature ustanovljeno je da MRI ima visoku detekciju prilikom dijagnostike adenoma hipofize. Kompjuterizirana tomografija ostaje metoda izbora kada magnetna rezonanca nije dostupna i u slučajevima kada se ona ne može uraditi. Korištenjem dinamskog CT-a poboljšava se detekcija mikroadenoma u odnosu na protokol snimanja hipofize magnetnom rezonancom.

In the last decade, there have been many reports on the negative impact of wildfires on various ecosystems. Unfortunately, wildfires have been intensifying as global temperatures, droughts, and other instances of extreme weather events rise around the world. These circumstances are forcing communities to vigorously address the uncontrolled spread of wildfires, where the ultimate goal is the protection of wildlife. At the same time, many disaster prevention and monitoring methods, based on image processing and computer vision, have been developed. In this paper, we present a new unsupervised method based on RGB color space for the early detection of wildfires from still images. From the analysis of existing state-of-the-art methods, it is evident that different methods explore different color spaces for the extraction of flame features. Our motivation was to use only RGB color space and thus eliminate the time-consuming task of color space conversion. The proposed method consists of several new image processing techniques used to efficiently extract flame features. It outperforms the existing methods, where an increase of 3% and 2% is recorded in the F1 score and Matthews correlation coefficient, respectively. Such performance demonstrates the merits of the proposed method for flame segmentation and detection.

A malignant peripheral nerve sheath tumour (MPNST) is a highly aggressive sarcoma. This disease develops in a number of people with neurofibromatosis type 1 (NF1), which is a common genetic disease. The paper presents a patient with typical manifestations of a malignant tumour of the peripheral nerve sheath, in the form of a large tumour of primary localisation in the distal part of the left thigh and left popliteal fossa and with significant dissemination into the lung parenchyma, which was accompanied by respiratory risk. The first operation of the tumour was done four years earlier, after which the patient did not come for regular check-ups. Nine cycles of chemotherapy were performed by Doxorubicin / Ifosfamide / Mesna protocol with clinical improvement and stabilisation, but without a significant impact on the dynamics of the disease and the overall survival was 14 months. It is of utmost importance to early recognise clinical presentation of the malignant form of this tumour and active supervision of a patient with a benign form by experts. In this way, it is possible to apply the optimal treatment modality in a timely manner.

Background/Aim: Therapy of diabetes mellitus type 2 includes drugs that act as inhibitors of dipeptidyl peptidase 4 (DPP-4) enzyme. Several DPP-4 inhibitors are marketed today and although they have favourable safety profile and tolerability, they show moderate activity in controlling glycaemia. The 3D quantitative structure-activity relationship (3D-QSAR) methodology was employed in order to find pharmacophore responsible for good DPP-4 inhibitory activity and designed new compounds with enhanced activity. Methods: For 3D-QSAR model development, 48 compounds structurally related to sitagliptin were collected from ChEMBL database. Structures of all compounds were optimised in order to find the best 3D conformations prior to QSAR modelling. To establish correlation between structure and biological activity Partial Least Squares (PLS) regression method integrated in Pentacle software was used. Results: Parameters of internal and external validation (R2 = 0.80, Q2 = 0.64 and R2 pred = 0.610) confirmed reliability of developed QSAR model. Analysis of obtained structural descriptors enabled identification of key structural characteristics that influenced DPP-4 inhibitory activity. Based on that information, new compounds were designed, of which 35 compounds had a better predicted activity, compared to sitagliptin. Conclusion: This QSAR model can be used for DPP-4 inhibitory activity prediction of structurally related compounds and resulting pharmacophore contains information useful for optimisation and design of new DPP-4 inhibitors. Finally, authors propose designed compounds for further synthesis, in vitro and in vivo testing, as new potential DPP-4 inhibitors.