Coral reefs

Koraljni grebeni su žrtve klimatskih promjena i zagađenja. Koralj je živo biće koje obitava u toplijim morima na dubinama do 50 metara i na temperaturama oko 18ºC. Koraljni grebeni su ekosistem u kojima u simbiozi žive različite vrste živih bića iz podmorskog svijeta. Posljednjih dvadeset i pet godina ugroženi su pojavom koja se naziva izbjeljivanje. Veliki koraljni greben svakako je jedan od najživljih i najljepših ekosustava na svijetu. Koraljni grebeni su najveće i najspektakularnije strukture stvorene od živih organizama. Iako izgledaju poput neuništivih, monumentalnih građevina, oni su tek krhak proizvod beskralješnjaka iz roda žarnjaka. Uz kišne šume, to je ujedno i najmnogovrsniji živući sistem na planetu. Koraljni greben može podnijeti oluje i bješnjenje mora, ali na početku 21. stoljeća najvećoj opasnosti izlaže ga čovjek. „Kolijevka Mnoštvu Vrsta Tisućljećima Stvarano Za Trenutak Uništeno” Jim MorrisCoral reefs are the victims of global warming and pollution. Coral are organisms which live in depth of 50 m and in temperatures of 18ºC. Coral reefs are ecosystem in which lives many organisms. Last 25 years they have been destroyed by bleaching. Great Barrier Reef is the most vivid and beautiful ecosystem in the world. Coral reefs are the biggest and most spectacular structures made by living organisms. They seem to look unbreakable and monumental structures, but they are fragile products of cnidaria. Besides rain forest, coral reef have high biodiversity of species. Coral reef can survive storms and powerful waves, but in the 21.century the greatest threat are humans. " Cradle to Myriads of Species Millennia to Create Moments to Destroy " Jim Morri

OPTIMIZATION AND APPROXIMATION OF NC POLYNOMIALS WITH SUMS OF SQUARES

In this paper we study eigenvalue optimization of non-commutative polynomials. That is, we compute the smallest or biggest eigenvalue a non-commutative polynomial can attain. Our algorithm is based on sums of hermittian squares. To test for exactness, the solutions of the dual SDP are investigated. When we consider the eigenvalue lower bounds we can show that attainability of the optimal value on the dual side implies that the eigenvalue bound is attained. We also show how to extract global eigenvalue optimizers with a procedure based on two ingredients: - the first is the solution to the truncated (tracial) moment problem; - the second is the Gelfand-Naimark-Segal (GNS) construction. The implementation of these procedures in our computer algebra system NC-SOStools is presented and several examples pertaining to matrix inequalities are given to illustrate the results

Fast-Flux Botnet Detection Based on Traffic Response and Search Engines Credit Worthiness

Botnets are considered as the primary threats on the Internet and there have been many research efforts to detect and mitigate them. Today, Botnet uses a DNS technique fast-flux to hide malware sites behind a constantly changing network of compromised hosts. This technique is similar to trustworthy Round Robin DNS technique and Content Delivery Network (CDN). In order to distinguish the normal network traffic from Botnets different techniques are developed with more or less success. The aim of this paper is to improve Botnet detection using an Intrusion Detection System (IDS) or router. A novel classification method for online Botnet detection based on DNS traffic features that distinguish Botnet from CDN based traffic is presented. Botnet features are classified according to the possibility of usage and implementation in an embedded system. Traffic response is analysed as a strong candidate for online detection. Its disadvantage lies in specific areas where CDN acts as a Botnet. A new feature based on search engine hits is proposed to improve the false positive detection. The experimental evaluations show that proposed classification could significantly improve Botnet detection. A procedure is suggested to implement such a system as a part of IDS

Promišljanja o prostornom identitetu grada iz perspektive promatrača

The article explores holistic approach of understanding that the concept of the city is not only material reality, it is also a mental structure that results subjective perception. Environmental perception differs during day and night. An empirical research was conducted, based on analytical method of mental mapping. The most often noticed points are pillars of city spatial identity. Their importance increases with occurrence frequency.Rad istražuje holistički pristup konceptu grada koji nadilazi materijalnu stvarnost i predstavlja mentalni konstrukt kao rezultat subjektivne percepcije. Percepcija okoliša različita je danju i noću. Provedeno je empirijsko istraživanje utemeljeno na analitičkoj metodi mentalnog mapiranja. Točke koje se najčešće percipiraju predstavljaju uporišne točke prostornog identiteta grada. Njihova važnost povećava se s učestalošću pojavljivanja

Photocatalytic degradation of nitrofurantoin

Mnogi farmaceutici i proizvodi za osobnu higijenu prepoznati su kao potencijalna zagađivala okoliša diljem svijeta. Skupina antibiotika, poznata kao nitrofurani (furaltadon, furazolidon, nitrofurantoin (NFT)) mogu se pronaći u okolišu zbog svoje velike proizvodnje i uporabe. Zbog sve veće prisutnosti u vodenim sustavima, primjena naprednih oksidacijskih procesa igra važnu ulogu u uklanjanju farmaceutika iz otpadnih voda. U ovom radu istraživana je fotokemijska razgradnja antibiotika nitrofurantoina primjenom direktne fotolize kao i fotokatalitičke oksidacije s TiO2 u UV/Vis području. Fotokemijski eksperimenti izvedeni su u laboratorijskom reaktoru s vanjskim izvorom svjetlosti. Heterogena reakcijska smjesa, TiO2 suspenzija, miješana je pomoću kontinuiranog protoka kisika ili argona unutar reaktora. Razgradnja antibiotika praćena je tekućinskom kromatografijom visoke djelotvornosti i spektrofotometrijski. Također su promatrani učinci valnih duljina zračenja i prisutnost kisika i argona u slučaju direktne fotolize. Apsorpcijski spektri i kromatografski rezultati jasno upućuju na različite strukturne promjene početne molekule antibiotika tijekom direktne fotolize i fotokatalize s TiO2. Brzi, prvi stupanj direktne fotolize je fotoizomerizacija oko C-N dvostruke veze nakon kojeg slijedi spori drugi stupanj fotorazgradnje. Heterogena fotokatalitička razgradnja nitrofurantoina znatno je brža od fotolitičke razgradnje koju prati značajno smanjenje pH-vrijednosti. Primjenom spektrometrije masa identificiran je glavni razgradni produkt fotolitičke i fotokatalitičke razgradnje nitrofurantoina.Many pharmaceuticals and personal care products have been detected as aquatic pollutants all over the world. The class of compounds, known as the nitrofuran antibiotics (furaltadone, furazolidone, nitrofurantoin (NFT)) are expected to be found in environment based on their big production and use. Due to increasing presence in aquatic systems, application of advanced oxidation processes play important role in removal of pharmaceuticals from wastewaters. In this work, the aquatic photochemical degradation of nitrofurantoin was investigated by application of direct photolysis as well as photocatalytic oxidation with TiO2 in the UV/Vis range. Photochemical experiments were carried out in laboratory-scale reactor with external light source. The heterogeneous reaction mixture, TiO2 suspension was circulated by continuously bubbling oxygen or argon within the reactor. Degradation of antibiotic was investigated by high-performance liquid chromatography and spectrometry. The effects of the irradiation wavelengths and the presence of oxygen and argon were also studied in the case of direct photolysis. Spectral and chromatographic results clearly indicated that in direct photolysis the starting antibiotic compound underwent structural transformations strongly deviating from the reactions in the case of TiO2-mediated photocatalysis. The fast, first step of the direct photolysis is attributed to photoisometization around the C-N double bond, followed by a slow second step of the photodegradation. Heterogenous photocatalytic degradation of nitrofurantoin was much more faster than photolytic degradation accompanied by a considerable decrease of pH. The key degradation product of photolytic and photocatalytic degradation of nitrofurantoin was identified by application of mass spectrometry

Lightning Network

The thesis describes a solution to the scalability problem of the cryptocurrency Bitcoin. Some of the key elements that cryptocurrencies use are hash functions and public key cryptography. Technology that constitutes the basis, all cryptocurrenciencies are built upon, is Blockchain. The mechanisms that make it safe and useful in networks without the central authority are the ones that also limit the number of transactions that are possible. The main topic of the thesis is Lightning Network, a solution that uses a network of payment channels to allow for larger quantities of transactions to be processed. We focus on the new mechanism, channels with descending timelocks, that promises secure offchain transactions

Photocatalytic degradation of nitrofurantoin

Mnogi farmaceutici i proizvodi za osobnu higijenu prepoznati su kao potencijalna zagađivala okoliša diljem svijeta. Skupina antibiotika, poznata kao nitrofurani (furaltadon, furazolidon, nitrofurantoin (NFT)) mogu se pronaći u okolišu zbog svoje velike proizvodnje i uporabe. Zbog sve veće prisutnosti u vodenim sustavima, primjena naprednih oksidacijskih procesa igra važnu ulogu u uklanjanju farmaceutika iz otpadnih voda. U ovom radu istraživana je fotokemijska razgradnja antibiotika nitrofurantoina primjenom direktne fotolize kao i fotokatalitičke oksidacije s TiO2 u UV/Vis području. Fotokemijski eksperimenti izvedeni su u laboratorijskom reaktoru s vanjskim izvorom svjetlosti. Heterogena reakcijska smjesa, TiO2 suspenzija, miješana je pomoću kontinuiranog protoka kisika ili argona unutar reaktora. Razgradnja antibiotika praćena je tekućinskom kromatografijom visoke djelotvornosti i spektrofotometrijski. Također su promatrani učinci valnih duljina zračenja i prisutnost kisika i argona u slučaju direktne fotolize. Apsorpcijski spektri i kromatografski rezultati jasno upućuju na različite strukturne promjene početne molekule antibiotika tijekom direktne fotolize i fotokatalize s TiO2. Brzi, prvi stupanj direktne fotolize je fotoizomerizacija oko C-N dvostruke veze nakon kojeg slijedi spori drugi stupanj fotorazgradnje. Heterogena fotokatalitička razgradnja nitrofurantoina znatno je brža od fotolitičke razgradnje koju prati značajno smanjenje pH-vrijednosti. Primjenom spektrometrije masa identificiran je glavni razgradni produkt fotolitičke i fotokatalitičke razgradnje nitrofurantoina.Many pharmaceuticals and personal care products have been detected as aquatic pollutants all over the world. The class of compounds, known as the nitrofuran antibiotics (furaltadone, furazolidone, nitrofurantoin (NFT)) are expected to be found in environment based on their big production and use. Due to increasing presence in aquatic systems, application of advanced oxidation processes play important role in removal of pharmaceuticals from wastewaters. In this work, the aquatic photochemical degradation of nitrofurantoin was investigated by application of direct photolysis as well as photocatalytic oxidation with TiO2 in the UV/Vis range. Photochemical experiments were carried out in laboratory-scale reactor with external light source. The heterogeneous reaction mixture, TiO2 suspension was circulated by continuously bubbling oxygen or argon within the reactor. Degradation of antibiotic was investigated by high-performance liquid chromatography and spectrometry. The effects of the irradiation wavelengths and the presence of oxygen and argon were also studied in the case of direct photolysis. Spectral and chromatographic results clearly indicated that in direct photolysis the starting antibiotic compound underwent structural transformations strongly deviating from the reactions in the case of TiO2-mediated photocatalysis. The fast, first step of the direct photolysis is attributed to photoisometization around the C-N double bond, followed by a slow second step of the photodegradation. Heterogenous photocatalytic degradation of nitrofurantoin was much more faster than photolytic degradation accompanied by a considerable decrease of pH. The key degradation product of photolytic and photocatalytic degradation of nitrofurantoin was identified by application of mass spectrometry

The patients experience of disease and control of the cardiovascular risk factors

Rezultati velikog broja istraživanja upućuju da već ustaljena medicinska praksa često pokazuje manjkavost po pitanju odnosa liječnika i bolesnika, jer ne dolazi do ispunjenja potreba i očekivanja bolesnika u procesu konzultacije. Težnja za objektivnošću i emocionalnom distanciranošću kod liječnika može dovesti do toga da bolesnik ne dolazi do izražaja tijekom konzultacije, a time se gubi važan spektar informacija koje uključuju bolesnikove emocije, ideje, poremećaje njegova funkcioniranja uslijed bolesti i očekivanja od liječnika. Posljedica toga jest narušen odnos između liječnika i bolesnika, a smanjena kooperativnost dovodi bolesnika u stanje nezadovoljstva i narušenog doživljaja bolesti, čime je povećana mogućnost problematičnog ishoda bolesti naročito ako uzmemo u obzir da su bolesnici tada skloniji nepridržavanju preporuka liječnika i neadherentnosti na propisanu terapiju. Posebice je niska adherentnost na preporučeno liječenje kardiovaskularnih (KV) bolesti što je istaknuti javnozdravstveni problem u skrbi za ove bolesnike. Budući da velik dio dnevnih odluka vezanih uz kontrolu KV čimbenika rizika donosi sam bolesnik, od velike je važnosti razumjeti bolesnikov doživljaj bolesti kao njegov odgovor na bolest i identificirati čimbenike vezane uz bolesnika koji utječu na kontrolu KV čimbenika rizika te posljedično na stupanj kontrole bolesti, sa svrhom unapređenja ishoda liječenja ovih bolesti. No također, i sami liječnici su nerijetko limitirani u postupcima koje mogu učiniti u vezi neke bolesti, međutim, uključivanjem gore navedenih komponenti povećava se i njihova mogućnost djelovanja. Iz toga proizlazi potreba za ostvarenjem dijaloga na ravnopravnoj razini, gdje se težnja prebacuje na poštovanje, razumijevanje, međusobno uvažavanje te dogovor oko postupaka liječenja.Due to numerous studies results, today we can conclude with certainty that the established medical practice shows certain fallacies regarding the relationship between the doctor and the patient, since the needs and expectations of the latter are not met in the consultation process. Striving for objectivity and emotional distance on the doctor's behalf can lead to the patient not being heard during the consultations, which in turn leads to the loss of an important range of information, including the patient's emotions, ideas, functional disorders caused by the disease, and his expectations of the doctor. The consequence thereof is a disturbed doctor-patient relationship, and the reduced cooperation brings the patient into a state of dissatisfaction and skews his experience of the disease. Consequently, the possibility of a problematic outcome of the disease increases, especially if we take into consideration that in such cases patients are more likely not to follow the doctor's orders and not to adhere to the recommended treatment. Adherence to the recommended treatment of cardiovascular (CV) diseases is especially low, which is a noted and notable public health issue when caring for such patients. Since the patient himself decides on most of the daily issues related to the control of CV risk factors, understanding his experience of the disease and seeing it as his response to the disease is of paramount importance. It is therefore highly important to identify the patient-related factors that influence the control of CV risk factors and of the disease itself, all with the purpose of improving the possible outcome of the treatment. The doctors themselves are often limited when it comes to what they can and cannot do about a certain disease; however, by including the aforementioned components, their action range is expanded. Therefore derives the need to establish a dialogue on equal footing, with an emphasis on mutual respect, acceptance, understanding, and agreement on the treatment process

Feminist Standpoint Theory

Epistemologija jest filozofska disciplina koja proučava i evaluira različite vrste znanja te uvjete pod kojima je znanje ostvarivo. Načela i obilježja tradicionalne epistemologije predmet su kritike u okviru feminističke teorije zbog perpetuiranja androcentrizma u znanosti i devaluiranja iskustava i doprinosa žena. Feministička epistemologija kroz svoja tri pravca – feministički empirizam, feministički postmodernizam te feminističku teoriju stajališta – preispituje prevladavajuće postavke znanosti poput objektivnosti i neutralnosti koje onemogućavaju ženama, ali i pripadnicima ostalih nedominantnih društvenih skupina, da doprinesu znanosti. Feministička teorija stajališta zastupa tezu o situiranosti znanja, tvrdeći kako znanstvene teorije i znanje nisu neutralni, nego su produkt društvenih i političkih utjecaja. Članovi deprivilegiranih društvenih skupina imaju bolji uvid u društvene okolnosti te mogućnost doći do istinitijih viđenja svijeta. Feministička teorija stajališta razvila se pod utjecajem pragmatizma i socijalnog konstruktivizma, a kritizira brojne postavke zapadne filozofske tradicije, smatrajući da su doprinijele diskriminatornom odnosu prema ženama. Pod utjecajem marksističke teorije razvio se feministički historijski materijalizam koji naglašava sličnost između položaja proleterijata u kapitalizmu i žena u androcentričnome društvu koje negira njihov epistemički autoritet. Pridavanje epistemičkog autoriteta ne treba isključivo vezati uz epistemičku povlaštenost, nego on treba biti dodijeljen svim osobama koje do sada nisu bile uključene u produkciju znanja