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Charm- and bottom-quark production in Au+Au collisions at √=200 GeV
No full textThe invariant yield of electrons from open-heavy-flavor decays for 1<<8 GeV/ at midrapidity ||<0.35 in Au+Au collisions at √ = 200 GeV has been measured by the PHENIX experiment at the BNL Relativistic Heavy Ion Collider. A displaced-vertex analysis with the PHENIX silicon-vertex detector enables extraction of the fraction of charm and bottom hadron decays and unfolding of the invariant yield of parent charm and bottom hadrons. The nuclear-modification factors for electrons from charm and bottom hadron decays and heavy-flavor hadrons show both a centrality and a quark-mass dependence, indicating suppression in the quark-gluon plasma produced in these collisions that is medium sized and quark-mass dependent
Ecology of the golden jackal (Canis aureus Linnaeus, 1758) and interspecific relationships with sympatric carnivores
No full textZlatni čagalj (Canis aureus Linneaus, 1758) je najveća i prostorno najraširenija vrsta čaglja te jedina koja se može pronaći izvan Afrike. Srednje veliki je sisavac koji pripada porodici pasa (Canidae) i redu zvijeri (Carnivora). Posljednjih godina, čagalj se naglo proširio Europom te formirao stabilne populacije uz najveću gustoću na području istočnog i središnjeg Balkana. Hrvatsku nastanjuje podvrsta europsko-maloazijski čagalj (Canis aureus moreoticus I. Geofrry Saint-Hilaire, 1835) koji se u najvećoj brojnosti može pronaći na sjeveru i jugu Dalmacije te u istočnoj Hrvatskoj. Čagalj je karnivor, no prema načinu života smatra se oportunistom i omnivorom koji prednost mahom daje najlakše dostupnoj hrani. Primarno jede hranu životinjskog podrijetla, no važan dio prehrana mu čine i biljne vrste te strvine. Prilagođen je različitim tipovima staništa, pa i ona u blizini ljudskih naselja, no u pravilu izbjegava staništa koje naseljava vuk. Čagalj ponekad dijeli staništa s drugim karnivorima koji imaju potrebe za sličnim resursima. Najčešće su to lisica, ris i vuk s kojima onda ulazi u različite interspecijske interakcije kao što su kompeticija i koegzistencija.The golden jackal (Canis aureus Linnaeus, 1758) is the largest and most widely distributed species of jackals and the only one that can be found outside Africa. It is a medium-sized mammal that belongs to the family of dogs (Canidae) and the order of beasts (Carnivora). In recent years, jackals have rapidly spread across Europe and formed stable populations with the highest density in the area of the eastern and central Balkans. Croatia is inhibited by the subspecies of the European jackal (Canis aureus moreoticus I. Geofrry Saint-Hilaire, 1835), which can be found in highest population density in the north and south of Dalmatia and in eastern Croatia. Jackal is a carnivore, but according to its lifestyle, it is considered an opportunist and an omnivore, which generally prefers the most readily available food. Its primarily food source is of animal origin, but an important part of its diet are also plant species and carrion. Jackals are adapted to different types of habitats, including those near human settlements, but it generally avoids habitats inhabited by wolves. Jackals can share habitats with other carnivores that have similar resource needs. Most often foxes, lynxes and wolves, with which various interspecies interactions take place such as competition and coexistence
Development potentials of Podravina region with a focus on rural tourism
No full textOvaj rad istražuje razvojne potencijale Podravine, s posebnim fokusom na ruralni turizam, uz analizu ključnih sektora poput poljoprivrede, turizma i industrije. Naglasak je stavljen na mogućnosti održivog razvoja putem optimalnog korištenja prirodnih resursa. Identificirani su glavni izazovi te su predložene mogućnosti za poboljšanje gospodarskog rasta i društvene kohezije u regiji. Zaključuje se da Podravina posjeduje značajan razvojni potencijal, osobito u ruralnom turizmu, koji se može ostvariti kroz integrirane pristupe i suradnju lokalnih zajednica, poduzetnika i javnih institucija.This paper explores the development potentials of the Podravina region, with a particular focus on rural tourism, while also analyzing key sectors such as agriculture and industry. Emphasis is placed on the possibilities for sustainable development through optimal use of natural resources and the promotion of innovation. The main challenges are identified, and strategies are proposed to enhance economic growth and social cohesion in the region. The conclusion is that Podravina possesses significant development potential, particularly in rural tourism, which can be realized through integrated approaches and collaboration between local communities, entrepreneurs, and public institutions
The use of recombinant DNA technology in gene therapy
No full textRekombinantna DNA tehnologija predstavlja niz metoda s kojima je moguće prenijeti gene iz jednog organizma u drugi. Prijenosom gena, protein koji se stvarao u početnom organizmu sada se stvara i u drugom. Jedna od primjena tehnologije rekombinantne DNA je u postupku genske terapije. Genska terapija je postupak u kojem se strana DNA, DNA koja sadrži gen od interesa, ubacuje u ljudske stanice s ciljem liječenja bolesti ili poremećaja. Za unos strane DNA postoje razne metode, a najuspješnija je korištenjem virusnih vektora. Genska terapija je revolucionarna metoda koja omogućuje liječenje genetskih bolesti.Recombinant DNA technology represents a number of methods by which it is possible to transfer genes from one organism to another. By gene transfer, the protein that was created in one organism is now created in the other one. One of the uses of recombinant DNA technology is the process of gene therapy. Gene therapy is a procedure in which foreign DNA, DNA containing the gene of interest, is inserted into human cells with the aim of treating a disease or disorder. Various methods are used to introduce foreign DNA, and the most successful is the use of viral vectors. Gene therapy is a revolutionary method that enables the treatment of genetic diseases
Implementation of quantum algorithms
No full textKvantno računanje prvo se pojavilo s idejom lakšeg simuliranja prirodnih kvantnih procesa za što treba ogromna količina klasičnih resursa. Od početaka do danas to područje je formalizirano u vidu kvantne teorije informacije i pokazalo se da postoje neki problemi koje bi takav pristup mogao riješiti efikasnije od bilo kojeg poznatog klasičnog algoritma. Najpoznatiji takav primjer je Shorov algoritam za faktoriziranje cijelih brojeva koji je privukao veliku pažnju javnosti zbog potencijalne primjene na razbijanje kriptografije. U ovom radu dan je teorijski uvod u kvantnu teoriju informacije i opisani su principi kojima kvantno računanje stječe eventualnu prednost nad klasičnim. Ukratko je dan osvrt na postojeća hardverska rješenja i na tehnike kojima se može poboljšati njihova pouzdanost. Objašnjen je Deutschev problem i pokazano je kako implementirati Deutschev algoritam formalizmom kvantnih krugova koristeći Qiskit paket u Pythonu. Detaljno je objašnjen Harrow - Hassidim - Lloyd (HHL) algoritam za rješavanje sustava linearnih jednadžbi i sve njegove subrutine koji je zatim primijenjen na konkretan linearni sustav dimenzija 2 × 2 i pokazana je implementacija svih kvantnih logičkih vrata potrebnih za to. Pripremljeni kvantni krug izvršen je uzorkovanjem, simuliranjem na klasičnom računalu i na stvarnom IBM-ovom kvantnom računalu. Usporedbom rezultata klasične simulacije i stvarnog mjerenja na kvantnom računalu dobivamo uvid u izazove koji stoje pred kvantnim računanjem prije nego ono postane pouzdana metoda računanja na velikim skalama. Klasičnom simulacijom pokazana je poanta HHL algoritma, a izvedbom na stvarnom kvantnom računalu vidljiva je eksperimentalna nesavršenost realnih qubita i njihova podložnost smetnjama i dekoherenciji.Quantum computing first emerged with the idea of facilitating the simulation of natural quantum processes, which requires an immense amount of classical resources. From its beginnings until today, this field has been formalized as quantum information theory, and it has been shown that there are some problems that such an approach could solve more efficiently than any known classical algorithm. The most famous example of this is Shor’s algorithm for factoring integers, which attracted significant public attention due to its potential application in breaking cryptography. In this paper, a theoretical introduction to quantum information theory is provided, and the principles by which quantum computing could gain an advantage over classical computing are described. A brief overview is given of existing hardware solutions and techniques that can improve their reliability. Deustch’s problem is explained, along with a demonstration of how to implement Deutsch’s algorithm using the formalism of quantum circuits with the Qiskit package in Python. The Harrow–Hassidim–Lloyd (HHL) algorithm for solving systems of linear equations is explained in detail, including all its subroutines, and is then applied to a specific 2×2 linear system, with a step-by-step implementation of all the quantum logic gates needed. The prepared quantum circuit was executed through sampling, simulation on a classical computer, and on a real IBM quantum computer. By comparing the results from classical simulation and actual measurement on a quantum computer, we gain insight into the challenges that quantum computing faces before it can become a reliable method for large-scale computation. The classical simulation demonstrates the essence of the HHL algorithm, while the execution on a real quantum computer reveals the experimental imperfections of real qubits and their susceptibility to interference and decoherence
Geochemical characterization of soils influenced by industrial waste
No full textOdlagalište otpadne lužine i crvenog mulja na području nekadašnje tvornice Jadral u Obrovcu i odlagalište čeličnog otpada tvornice čelika u Sisku su odlagališta industrijskih otpada s visokim udjelom metala. U ovom radu, geokemijski je karakterizirano 10 uzoraka tla sakupljenih u okolici navedenih odlagališta. Na svakom uzorku provedena je granulometrijska, mineraloška i multielementna analiza te površinsko fizikalno-kemijski karakterizacija tla određivanjem specifične površine i kapaciteta kationske izmjene. Granulometrijska analiza provedena je metodom laserske difrakcije. Mineralni sastav sedimenta istražen je metodom rendgenske difrakcije u prahu na rendgenskom difraktometru s CuKα zračenjem i grafitnim monokromatorom. Kapacitet kationske izmjene određen je amonij selektivnom elektrodom. Specifične površine uzoraka određene su na instrumentu FlowSorb II 2300. Multielementna analiza provedena je na trostrukom kvadrupolnom spektrometru masa uz induktivno spregnutu plazmu. U svim uzorcima analizirane su koncentracije 11 elemenata (As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Sb, V, Zn). Unatoč visokim koncentracijama metala koje su pokazali rezultati u uzorcima tla na oba lokaliteta, zbog manje površinske reaktivnosti čestica u istraživanim tlima na području Željezare Sisak, kao i vezanosti metala u tlima na području Jadrala u Fe/Mn okside koji se u normalnim okolišnim uvjetima ne izlužuju u okoliš, može se zaključiti da, ukoliko ne dođe do značajnije promjene okolišnih uvjeta, čestice tla iz oba područja istraživanja vjerojatno neće otpustiti značajnije koncentracije metala u okoliš.Waste base and red mud disposal site near the former Jadral factory in Obrovac and steel waste disposal site of steel plant in Sisak are disposal sites of industrial waste with a high metal content. In this paper, 10 soil samples collected near the mentioned disposal sites were geochemically characterized. On each sample was performed granulometrical, mineralogical and multielement analysis, as well as surface physico-chemical characterization of the soil by determining the specific surface area and cation exchange capacity. Granulometric analysis was performed using the laser diffraction method. Mineral composition of the sediment was investigated using X-ray powder diffraction on an X-ray diffractometer with CuKα radiation and a graphite monochromator. Cation exchange capacity was determined by an ammonium selective electrode. Specific surfaces of the samples were determined on a FlowSorb II 2300 instrument. Multielement analysis was performed on a triple quadrupole mass spectrometer with inductively coupled plasma. Concentrations of 11 elements (As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Sb, V, Zn) were analyzed in all samples. Despite the high concentrations of metals that were shown in the soil samples at both locations, due to the lower surface reactivity of the particles in the investigated soils in the Sisak steel plant area, as well as the binding of metals in the soils in the Jadral area to Fe/Mn oxides that do not leach out into the environment under normal environmental conditions, it can be concluded that, unless significant changes in environmental conditions occur, soil particles from both research areas will probably not allow significant concentrations of metals in the environment
Perfect numbers
No full textSavršeni brojevi interesantan su dio teorije brojeva. Matematičari ih godinama istražuju, no još uvijek nije poznata njihova primjena. Usko vezani uz savršene brojeve su i Mersenneovi brojevi. Jedan od načina pronalaska savršenih brojeva je pronalazak nešto jednostavnijih Mersenneovih prostih brojeva. U ovom diplomskom radu navedeni su matematički temelji potrebni za razumijevanje istoga. Nakon toga slijede definicija i svojstva Mersenneovih brojeva te se spominje i opisuje Lucas--Lehmerov test provjere prostosti. Naposljetku se govori o savršenim brojecima, njihovim svojstvima, višestruko savršenim brojevima te uvjetima koje bi neparni savršeni brojevi trebali zadovoljavati ukoliko postoje.Perfect numbers are an interesting part of number theory. Mathematicians have been researching them for years, but their application is still unknown. Closely related to perfect numbers are Mersenne numbers. One way to find perfect numbers is to find the simpler Mersenne primes. This thesis presents the mathematical foundations necessary for understanding perfect numbers. This is followed by the definition and properties of Mersenne numbers, and the Lucas--Lehmer test for primality is mentioned and described. At the end, perfect numbers and their properties are discussed as well as multiply perfect numbers and conditions that odd perfect numbers should meet if they exist
Rytz construction and geometry of singular value decomposition
No full textU radu promatramo geometriju dekompozicije matrice odnosno linearnog operatora po singularnim vrijednostima (skraćeno SVD).
Singularne vrijednosti matrice su kvadratni korijeni svojstvenih vrijednosti hermitski simetrične, pozitivno definitne matrice . Ključna je činjenica da se dijagonalizira u ortonormiranoj bazi te da djelovanje na svojstvene vektore od čuva ortogonalnost. U SVD matrica tipa faktorizira se kao umnožak tri matrice, od kojih su one vanjske ortogonalne/unitarne, a srednja je jednakog tipa kao te sadrži dijagonalnu podmatricu sa singularnim vrijednostima na dijagonali. Geometrijski ta faktorizacija znači kompoziciju, redom, izometrije kojom se prelazi u ortonormiranu bazu svojstvenih vektora od , zatim skaliranja po smjerovima tih vektora te završno još jedne izometrije.
U euklidskoj ravnini SVD se primjenjuje na bijektivnu afinu transformaciju i njezino djelovanje na jediničnu kružnicu. Slika je elipsa, određena bilo kojim parom konjugiranih promjera kao slikom para ortogonalnih promjera kružnice. Rytzovom konstrukcijom dobivaju se glavne osi elipse, a duljine poluosi elipse jednake su singularnim vrijednostima operatora . Druga geometrijska primjena SVD odnosi se na kosu aksonometriju, to jest paralelnu projekciju euklidskog prostora na ravninu, u kojoj je zadana slika jedne ortonormirane baze prostora. Postupkom analognim prethodnom konstruiraju se projekcije prividne i stvarne konture jedinične sfere.In this thesis we examine the geometry of the singular values decomposition (SVD) of a matrix or a linear operator. The singular values of the matrix are the square roots of the eigenvalues of the Hermitian symmetric, positive definite matrix . The key fact is that is diagonalized in an orthonormal basis and the action of on the eigenvectors of preserves orthogonality. In SVD, matrix of type is factorized as a product of three matrices, of which the outer one are orthogonal/unitary, and the middle one is of the same type as and contains a diagonal submatrix with singular values on the diagonal. Geometrically, this factorization means the composition, respectively, of an isometry, which is used for transition to the orthonormalized base of eigenvectors of , then scaling along the directions of these vectors, and finally another isometry.
In the Euclidean plane, SVD is applied to the bijective affine transformation and its action on the unit circle. The image is an ellipse, defined by any pair of conjugate diameters as the image of a pair of orthogonal diameters of a circle. The main axes of the ellipse are obtained by the Rytz construction, and the lengths of the semi-axes of the ellipse are equal to the singular values of the operator . Another geometric application of SVD refers to oblique axonometry, that is, the parallel projection of Euclidean space onto a plane, in which the image of an orthonormal base of space is given. Using a similar procedure, projections of the apparent and real contours of the unit sphere are constructed